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Python Data Types: Dictionary - Exercises, Practice, Solution

Python Dictionary [ 80 exercises with solution]

Python dictionary is a container of the unordered set of objects like lists. The objects are surrounded by curly braces { }. The items in a dictionary are a comma-separated list of key:value pairs where keys and values are Python data type.

You may read our Python dictionary tutorial before solving the following exercises.

[An editor is available at the bottom of the page to write and execute the scripts.]

1. Write a Python script to sort (ascending and descending) a dictionary by value. Go to the editor

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2. Write a Python script to add a key to a dictionary. Go to the editor

Sample Dictionary : {0: 10, 1: 20}
Expected Result : {0: 10, 1: 20, 2: 30}

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3. Write a Python script to concatenate the following dictionaries to create a new one. Go to the editor

Sample Dictionary :
dic1={1:10, 2:20}
dic2={3:30, 4:40}
dic3={5:50,6:60}
Expected Result : {1: 10, 2: 20, 3: 30, 4: 40, 5: 50, 6: 60}

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4. Write a Python script to check whether a given key already exists in a dictionary. Go to the editor

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5. Write a Python program to iterate over dictionaries using for loops. Go to the editor

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6. Write a Python script to generate and print a dictionary that contains a number (between 1 and n) in the form (x, x*x). Go to the editor
Sample Dictionary ( n = 5) :
Expected Output : {1: 1, 2: 4, 3: 9, 4: 16, 5: 25}
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7. Write a Python script to print a dictionary where the keys are numbers between 1 and 15 (both included) and the values are the square of the keys. Go to the editor
Sample Dictionary
{1: 1, 2: 4, 3: 9, 4: 16, 5: 25, 6: 36, 7: 49, 8: 64, 9: 81, 10: 100, 11: 121, 12: 144, 13: 169, 14: 196, 15: 225}
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8. Write a Python script to merge two Python dictionaries. Go to the editor
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9. Write a Python program to iterate over dictionaries using for loops. Go to the editor
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10. Write a Python program to sum all the items in a dictionary. Go to the editor
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11. Write a Python program to multiply all the items in a dictionary. Go to the editor
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12. Write a Python program to remove a key from a dictionary. Go to the editor
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13. Write a Python program to map two lists into a dictionary. Go to the editor
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14. Write a Python program to sort a given dictionary by key. Go to the editor
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15. Write a Python program to get the maximum and minimum values of a dictionary. Go to the editor
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16. Write a Python program to get a dictionary from an object's fields. Go to the editor
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17. Write a Python program to remove duplicates from the dictionary. Go to the editor
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18. Write a Python program to check if a dictionary is empty or not. Go to the editor
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19. Write a Python program to combine two dictionary by adding values for common keys. Go to the editor
d1 = {'a': 100, 'b': 200, 'c':300}
d2 = {'a': 300, 'b': 200, 'd':400}
Sample output: Counter({'a': 400, 'b': 400, 'd': 400, 'c': 300})
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20. Write a Python program to print all distinct values in a dictionary. Go to the editor
Sample Data : [{"V":"S001"}, {"V": "S002"}, {"VI": "S001"}, {"VI": "S005"}, {"VII":"S005"}, {"V":"S009"},{"VIII":"S007"}]
Expected Output : Unique Values: {'S005', 'S002', 'S007', 'S001', 'S009'}
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21. Write a Python program to create and display all combinations of letters, selecting each letter from a different key in a dictionary. Go to the editor
Sample data : {'1':['a','b'], '2':['c','d']}
Expected Output:
ac
ad
bc
bd
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22. Write a Python program to find the highest 3 values of corresponding keys in a dictionary. Go to the editor
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23. Write a Python program to combine values in a list of dictionaries. Go to the editor
Sample data: [{'item': 'item1', 'amount': 400}, {'item': 'item2', 'amount': 300}, {'item': 'item1', 'amount': 750}]
Expected Output: Counter({'item1': 1150, 'item2': 300})
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24. Write a Python program to create a dictionary from a string. Go to the editor
Note: Track the count of the letters from the string.
Sample string : 'w3resource'
Expected output: {'w': 1, '3': 1, 'r': 2, 'e': 2, 's': 1, 'o': 1, 'u': 1, 'c': 1}
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25. Write a Python program to print a dictionary in table format. Go to the editor
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26. Write a Python program to count the values associated with a key in a dictionary. Go to the editor
Expected Output:
6
2
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27. Write a Python program to convert a list into a nested dictionary of keys. Go to the editor
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28. Write a Python program to sort a list alphabetically in a dictionary. Go to the editor
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29. Write a Python program to remove spaces from dictionary keys. Go to the editor
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30. Write a Python program to get the top three items in a shop. Go to the editor
Sample data: {'item1': 45.50, 'item2':35, 'item3': 41.30, 'item4':55, 'item5': 24}
Expected Output:
item4 55
item1 45.5
item3 41.3
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31. Write a Python program to get the key, value and item in a dictionary. Go to the editor
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32. Write a Python program to print a dictionary line by line. Go to the editor
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33. Write a Python program to check if multiple keys exist in a dictionary. Go to the editor
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34. Write a Python program to count the number of items in a dictionary value that is a list. Go to the editor
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35. Write a Python program to sort Counter by value. Go to the editor
Sample data : {'Math':81, 'Physics':83, 'Chemistry':87}
Expected data: [('Chemistry', 87), ('Physics', 83), ('Math', 81)]
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36. Write a Python program to create a dictionary from two lists without losing duplicate values. Go to the editor
Sample lists: ['Class-V', 'Class-VI', 'Class-VII', 'Class-VIII'], [1, 2, 2, 3]
Expected Output: defaultdict(<class 'set'>, {'Class-V': {1}, 'Class-VI': {2}, 'Class-VII': {2}, 'Class-VIII': {3}})
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37. Write a Python program to replace dictionary values with their sums. Go to the editor
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38. Write a Python program to match key values in two dictionaries. Go to the editor
Sample dictionary: {'key1': 1, 'key2': 3, 'key3': 2}, {'key1': 1, 'key2': 2}
Expected output: key1: 1 is present in both x and y
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39. Write a Python program to store dictionary data in a JSON file. Go to the editor
Original dictionary:
{'students': [{'firstName': 'Nikki', 'lastName': 'Roysden'}, {'firstName': 'Mervin', 'lastName': 'Friedland'}, {'firstName': 'Aron ', 'lastName': 'Wilkins'}], 'teachers': [{'firstName': 'Amberly', 'lastName': 'Calico'}, {'firstName': 'Regine', 'lastName': 'Agtarap'}]}
<class 'dict'>
Json file to dictionary:
{'students': [{'firstName': 'Nikki', 'lastName': 'Roysden'}, {'firstName': 'Mervin', 'lastName': 'Friedland'}, {'firstName': 'Aron ', 'lastName': 'Wilkins'}], 'teachers': [{'firstName': 'Amberly', 'lastName': 'Calico'}, {'firstName': 'Regine', 'lastName': 'Agtarap'}]}
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40. Write a Python program to create a dictionary of keys x, y, and z where each key has as value a list from 11-20, 21-30, and 31-40 respectively. Access the fifth value of each key from the dictionary. Go to the editor
{'x': [11, 12, 13, 14, 15, 16, 17, 18, 19],
'y': [21, 22, 23, 24, 25, 26, 27, 28, 29],
'z': [31, 32, 33, 34, 35, 36, 37, 38, 39]}
15
25
35
x has value [11, 12, 13, 14, 15, 16, 17, 18, 19]
y has value [21, 22, 23, 24, 25, 26, 27, 28, 29]
z has value [31, 32, 33, 34, 35, 36, 37, 38, 39]
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41. Write a Python program to drop empty items from a given dictionary. Go to the editor
Original Dictionary:
{'c1': 'Red', 'c2': 'Green', 'c3': None}
New Dictionary after dropping empty items:
{'c1': 'Red', 'c2': 'Green'}
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42. Write a Python program to filter a dictionary based on values. Go to the editor
Original Dictionary:
{'Cierra Vega': 175, 'Alden Cantrell': 180, 'Kierra Gentry': 165, 'Pierre Cox': 190}
Marks greater than 170:
{'Cierra Vega': 175, 'Alden Cantrell': 180, 'Pierre Cox': 190}
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43. Write a Python program to convert more than one list to a nested dictionary. Go to the editor
Original strings:
['S001', 'S002', 'S003', 'S004']
['Adina Park', 'Leyton Marsh', 'Duncan Boyle', 'Saim Richards']
[85, 98, 89, 92]
Nested dictionary:
[{'S001': {'Adina Park': 85}}, {'S002': {'Leyton Marsh': 98}}, {'S003': {'Duncan Boyle': 89}}, {'S004': {'Saim Richards': 92}}]
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44. Write a Python program to filter the height and width of students, which are stored in a dictionary. Go to the editor
Original Dictionary:
{'Cierra Vega': (6.2, 70), 'Alden Cantrell': (5.9, 65), 'Kierra Gentry': (6.0, 68), 'Pierre Cox': (5.8, 66)}
Height > 6ft and Weight> 70kg:
{'Cierra Vega': (6.2, 70)}
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45. Write a Python program to verify that all values in a dictionary are the same. Go to the editor
Original Dictionary:
{'Cierra Vega': 12, 'Alden Cantrell': 12, 'Kierra Gentry': 12, 'Pierre Cox': 12}
Check all are 12 in the dictionary.
True
Check all are 10 in the dictionary.
False
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46. Write a Python program to create a dictionary grouping a sequence of key-value pairs into a dictionary of lists. Go to the editor
Original list:
[('yellow', 1), ('blue', 2), ('yellow', 3), ('blue', 4), ('red', 1)]
Grouping a sequence of key-value pairs into a dictionary of lists:
{'yellow': [1, 3], 'blue': [2, 4], 'red': [1]}
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47. Write a Python program to split a given dictionary of lists into lists of dictionaries. Go to the editor
Original dictionary of lists:
{'Science': [88, 89, 62, 95], 'Language': [77, 78, 84, 80]}
Split said dictionary of lists into list of dictionaries:
[{'Science': 88, 'Language': 77}, {'Science': 89, 'Language': 78}, {'Science': 62, 'Language': 84}, {'Science': 95, 'Language': 80}]
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48. Write a Python program to remove a specified dictionary from a given list. Go to the editor
Original list of dictionary:
[{'id': '#FF0000', 'color': 'Red'}, {'id': '#800000', 'color': 'Maroon'}, {'id': '#FFFF00', 'color': 'Yellow'}, {'id': '#808000', 'color': 'Olive'}]
Remove id #FF0000 from the said list of dictionary:
[{'id': '#800000', 'color': 'Maroon'}, {'id': '#FFFF00', 'color': 'Yellow'}, {'id': '#808000', 'color': 'Olive'}]
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49. Write a Python program to convert string values of a given dictionary into integer/float datatypes. Go to the editor
Original list:
[{'x': '10', 'y': '20', 'z': '30'}, {'p': '40', 'q': '50', 'r': '60'}]
String values of a given dictionary, into integer types:
[{'x': 10, 'y': 20, 'z': 30}, {'p': 40, 'q': 50, 'r': 60}]
Original list:
[{'x': '10.12', 'y': '20.23', 'z': '30'}, {'p': '40.00', 'q': '50.19', 'r': '60.99'}]
String values of a given dictionary, into float types:
[{'x': 10.12, 'y': 20.23, 'z': 30.0}, {'p': 40.0, 'q': 50.19, 'r': 60.99}]
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50. A Python dictionary contains List as a value. Write a Python program to clear the list values in the said dictionary. Go to the editor
Original Dictionary:
{'C1': [10, 20, 30], 'C2': [20, 30, 40], 'C3': [12, 34]}
Clear the list values in the said dictionary:
{'C1': [], 'C2': [], 'C3': []}
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51. A Python Dictionary contains List as a value. Write a Python program to update the list values in the said dictionary. Go to the editor
Original Dictionary:
{'Math': [88, 89, 90], 'Physics': [92, 94, 89], 'Chemistry': [90, 87, 93]}
Update the list values of the said dictionary:
{'Math': [89, 90, 91], 'Physics': [90, 92, 87], 'Chemistry': [90, 87, 93]}
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52. Write a Python program to extract a list of values from a given list of dictionaries. Go to the editor
Original Dictionary:
[{'Math': 90, 'Science': 92}, {'Math': 89, 'Science': 94}, {'Math': 92, 'Science': 88}]
Extract a list of values from said list of dictionaries where subject = Science
[92, 94, 88]
Original Dictionary:
[{'Math': 90, 'Science': 92}, {'Math': 89, 'Science': 94}, {'Math': 92, 'Science': 88}]
Extract a list of values from said list of dictionaries where subject = Math
[90, 89, 92]
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53. Write a Python program to find the length of a dictionary of values. Go to the editor
Original Dictionary:
{1: 'red', 2: 'green', 3: 'black', 4: 'white', 5: 'black'}
Length of dictionary values:
{'red': 3, 'green': 5, 'black': 5, 'white': 5}
Original Dictionary:
{'1': 'Austin Little', '2': 'Natasha Howard', '3': 'Alfred Mullins', '4': 'Jamie Rowe'}
Length of dictionary values:
{'Austin Little': 13, 'Natasha Howard': 14, 'Alfred Mullins': 14, 'Jamie Rowe': 10}
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54. Write a Python program to get the depth of a dictionary. Go to the editor
Expected Output:
4
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55. Write a Python program to access dictionary key's element by index. Go to the editor
Expected Output:
physics
math
chemistry
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56. Write a Python program to convert a dictionary into a list of lists. Go to the editor
Original Dictionary:
{1: 'red', 2: 'green', 3: 'black', 4: 'white', 5: 'black'}
Convert the said dictionary into a list of lists:
[[1, 'red'], [2, 'green'], [3, 'black'], [4, 'white'], [5, 'black']]
Original Dictionary:
{'1': 'Austin Little', '2': 'Natasha Howard', '3': 'Alfred Mullins', '4': 'Jamie Rowe'}
Convert the said dictionary into a list of lists:
[['1', 'Austin Little'], ['2', 'Natasha Howard'], ['3', 'Alfred Mullins'], ['4', 'Jamie Rowe']]
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57. Write a Python program to filter even numbers from a dictionary of values. Go to the editor
Original Dictionary:
{'V': [1, 4, 6, 10], 'VI': [1, 4, 12], 'VII': [1, 3, 8]}
Filter even numbers from said dictionary values:
{'V': [4, 6, 10], 'VI': [4, 12], 'VII': [8]}
Original Dictionary:
{'V': [1, 3, 5], 'VI': [1, 5], 'VII': [2, 7, 9]}
Filter even numbers from said dictionary values:
{'V': [], 'VI': [], 'VII': [2]}
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58. Write a Python program to get all combinations of key-value pairs in a given dictionary. Go to the editor
Original Dictionary:
{'V': [1, 4, 6, 10], 'VI': [1, 4, 12], 'VII': [1, 3, 8]}
Combinations of key-value pairs of the said dictionary:
[{'V': [1, 4, 6, 10], 'VI': [1, 4, 12]}, {'V': [1, 4, 6, 10], 'VII': [1, 3, 8]}, {'VI': [1, 4, 12], 'VII': [1, 3, 8]}]
Original Dictionary:
{'V': [1, 3, 5], 'VI': [1, 5]}
Combinations of key-value pairs of the said dictionary:
[{'V': [1, 3, 5], 'VI': [1, 5]}]
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59. Write a Python program to find the specified number of maximum values in a given dictionary. Go to the editor
Original Dictionary:
{'a': 5, 'b': 14, 'c': 32, 'd': 35, 'e': 24, 'f': 100, 'g': 57, 'h': 8, 'i': 100}
1 maximum value(s) in the said dictionary:
['f']
2 maximum value(s) in the said dictionary:
['f', 'i']
5 maximum value(s) in the said dictionary:
['f', 'i', 'g', 'd', 'c']
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60. Write a Python program to find the shortest list of values for the keys in a given dictionary. Go to the editor
Original Dictionary: {'V': [10, 12], 'VI': [10], 'VII': [10, 20, 30, 40], 'VIII': [20], 'IX': [10, 30, 50, 70], 'X': [80]} Shortest list of values with the keys of the said dictionary: ['VI', 'VIII', 'X']
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61. Write a Python program to count the frequency of a dictionary. Go to the editor
Original Dictionary:
{'V': 10, 'VI': 10, 'VII': 40, 'VIII': 20, 'IX': 70, 'X': 80, 'XI': 40, 'XII': 20}
Count the frequency of the said dictionary:
Counter({10: 2, 40: 2, 20: 2, 70: 1, 80: 1})
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62. Write a Python program to extract values from a given dictionary and create a list of lists from those values. Go to the editor
Original Dictionary:
[{'student_id': 1, 'name': 'Jean Castro', 'class': 'V'}, {'student_id': 2, 'name': 'Lula Powell', 'class': 'V'}, {'student_id': 3, 'name': 'Brian Howell', 'class': 'VI'}, {'student_id': 4, 'name': 'Lynne Foster', 'class': 'VI'}, {'student_id': 5, 'name': 'Zachary Simon', 'class': 'VII'}]
Extract values from the said dictionarie and create a list of lists using those values:
[[1, 'Jean Castro', 'V'], [2, 'Lula Powell', 'V'], [3, 'Brian Howell', 'VI'], [4, 'Lynne Foster', 'VI'], [5, 'Zachary Simon', 'VII']]
[[1, 'Jean Castro'], [2, 'Lula Powell'], [3, 'Brian Howell'], [4, 'Lynne Foster'], [5, 'Zachary Simon']]
[['Jean Castro', 'V'], ['Lula Powell', 'V'], ['Brian Howell', 'VI'], ['Lynne Foster', 'VI'], ['Zachary Simon', 'VII']]
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63. Write a Python program to convert a given list of lists to a dictionary. Go to the editor
Original list of lists:
[[1, 'Jean Castro', 'V'], [2, 'Lula Powell', 'V'], [3, 'Brian Howell', 'VI'], [4, 'Lynne Foster', 'VI'], [5, 'Zachary Simon', 'VII']]
Convert the said list of lists to a dictionary:
{1: ['Jean Castro', 'V'], 2: ['Lula Powell', 'V'], 3: ['Brian Howell', 'VI'], 4: ['Lynne Foster', 'VI'], 5: ['Zachary Simon', 'VII']}
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64. Write a Python program that creates key-value list pairings within a dictionary. Go to the editor
Original dictionary:
{1: ['Jean Castro'], 2: ['Lula Powell'], 3: ['Brian Howell'], 4: ['Lynne Foster'], 5: ['Zachary Simon']}
A key-value list pairings of the said dictionary:
[{1: 'Jean Castro', 2: 'Lula Powell', 3: 'Brian Howell', 4: 'Lynne Foster', 5: 'Zachary Simon'}]
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65. Write a Python program to get the total length of all values in a given dictionary with string values. Go to the editor
Original dictionary:
{'#FF0000': 'Red', '#800000': 'Maroon', '#FFFF00': 'Yellow', '#808000': 'Olive'}
Total length of all values of the said dictionary with string values:
20
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66. Write a Python program to check if a specific key and a value exist in a dictionary. Go to the editor
Original dictionary:
[{'student_id': 1, 'name': 'Jean Castro', 'class': 'V'}, {'student_id': 2, 'name': 'Lula Powell', 'class': 'V'}, {'student_id': 3, 'name': 'Brian Howell', 'class': 'VI'}, {'student_id': 4, 'name': 'Lynne Foster', 'class': 'VI'}, {'student_id': 5, 'name': 'Zachary Simon', 'class': 'VII'}]
Check if a specific Key and a value exist in the said dictionary:
True
True
True
False
False
False
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67. Write a Python program to invert a given dictionary with non-unique hashable values. Go to the editor
Sample Output:
{8: ['Ora Mckinney', 'Mathew Gilbert'], 7: ['Theodore Hollandl', 'Mae Fleming', 'Ivan Little']}
Click me to see the sample solution

68. Write a Python program to combine two or more dictionaries, creating a list of values for each key. Go to the editor
Sample Output:
Original dictionaries:
{'w': 50, 'x': 100, 'y': 'Green', 'z': 400}
{'x': 300, 'y': 'Red', 'z': 600}
Combined dictionaries, creating a list of values for each key:
{'w': [50], 'x': [100, 300], 'y': ['Green', 'Red'], 'z': [400, 600]}
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69. Write a Python program to group the elements of a given list based on the given function. Go to the editor
Sample Output:
Original list & function:
[7, 23, 3.2, 3.3, 8.4] Function name: floor:
Group the elements of the said list based on the given function:
{7: [7], 23: [23], 3: [3.2, 3.3], 8: [8.4]}
Original list & function:
['Red', 'Green', 'Black', 'White', 'Pink'] Function name: len:
Group the elements of the said list based on the given function:
{3: ['Red'], 5: ['Green', 'Black', 'White'], 4: ['Pink']}
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70. Write a Python program to map the values of a given list to a dictionary using a function, where the key-value pairs consist of the original value as the key and the result of the function as the value. Go to the editor
Sample Output:
{1: 1, 2: 4, 3: 9, 4: 16}
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71. Write a Python program to retrieve the value of the nested key indicated by the given selector list from a dictionary or list. Go to the editor
Sample Output:
Russell
2
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72. Write a Python program to invert a dictionary with unique hashable values. Go to the editor
Sample Output:
{10: 'Theodore', 11: 'Mathew', 9: 'Roxanne'}
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73. Write a Python program to convert a list of dictionaries into a list of values corresponding to the specified key. Go to the editor
Sample Output:
Original list of dictionaries:
[{'name': 'Theodore', 'age': 18}, {'name': 'Mathew', 'age': 22}, {'name': 'Roxanne', 'age': 20}, {'name': 'David', 'age': 18}]
Convert a list of dictionaries into a list of values corresponding to the specified key:
[18, 22, 20, 18]
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74. Write a Python program to create a dictionary with the same keys as the given dictionary and values generated by running the given function for each value. Go to the editor
Sample Output:
Original dictionary elements:
{'Theodore': {'user': 'Theodore', 'age': 45}, 'Roxanne': {'user': 'Roxanne', 'age': 15}, 'Mathew': {'user': 'Mathew', 'age': 21}}
Dictionary with the same keys:
{'Theodore': 45, 'Roxanne': 15, 'Mathew': 21}
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75. Write a Python program to find all keys in a dictionary that have the given value. Go to the editor
Sample Output:
Original dictionary elements:
{'Theodore': 19, 'Roxanne': 20, 'Mathew': 21, 'Betty': 20}
Find all keys in the said dictionary that have the specified value:
['Roxanne', 'Betty']
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76. Write a Python program to combine two lists into a dictionary. The elements of the first one serve as keys and the elements of the second one serve as values. Each item in the first list must be unique and hashable. Go to the editor
Sample Output:
Original lists:
['a', 'b', 'c', 'd', 'e', 'f']
[1, 2, 3, 4, 5]
Combine the values of the said two lists into a dictionary:
{'a': 1, 'b': 2, 'c': 3, 'd': 4, 'e': 5}
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77. Write a Python program to transform a dictionary into a list of tuples. Go to the editor
Sample Output:
Original Dictionary:
{'Red': 1, 'Green': 3, 'White': 5, 'Black': 2, 'Pink': 4}
Convert the said dictionary to a list of tuples:
[('Red', 1), ('Green', 3), ('White', 5), ('Black', 2), ('Pink', 4)]
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78. Write a Python program to create a flat list of all the keys in a flat dictionary. Go to the editor
Sample Output:
Original dictionary elements:
{'Theodore': 19, 'Roxanne': 20, 'Mathew': 21, 'Betty': 20}
Create a flat list of all the keys of the said flat dictionary:
['Theodore', 'Roxanne', 'Mathew', 'Betty']
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79. Write a Python program to create a flat list of all the values in a flat dictionary. Go to the editor
Sample Output:
Original dictionary elements:
{'Theodore': 19, 'Roxanne': 20, 'Mathew': 21, 'Betty': 20}
Create a flat list of all the values of the said flat dictionary:
[19, 20, 21, 20]
Click me to see the sample solution

80. Write a Python program to find the key of the maximum value in a dictionary. Go to the editor
Sample Output:
Original dictionary elements:
{'Theodore': 19, 'Roxanne': 22, 'Mathew': 21, 'Betty': 20}
Finds the key of the maximum and minimum value of the said dictionary:
('Roxanne', 'Theodore')
Click me to see the sample solution

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Python: Tips of the Day

Serialization:

Sometimes you may need to save your Python object locally for later use or Network transfers. Python has fantastic libraries for serialization such as Json and Pickle.

Serialization is storing data structures in the program so they don't just disappear after the program is terminated.

There is also marshal library but it's more primitive and can't handle certain techniques such as class instances and recursion. Marshal is closer to json in its scope of serialization.

So, when would you use pickle, cpickle, json or ujson?

cpickle and ujson are faster versions of respective libraries that take advantage of C implementations in Python. So they'd always be favorable for speed reasons.

Apart from that, json is a more secure and readable version of serialization than pickle which comes at a cost of speed.

While you can take care of almost any data structure in Python with Json it gets inefficient with large files or uncommon objects. Pickle on the other hand operates in a sweet spot where you'd like to work with large files (multiple GBs) and still don't want to be bothered with database solutions.

The thing is depending on your application, you may have to watch out for security vulnerabilities pickle introduces to the system so it's usually wise to seek out json or database solutions before resorting to pickle when possible.

import pickle
lst = ["LST", "LGA", "SFO", "BOM", "JFK", "MIA"]
x = pickle.dumps(lst)
print(x)

Output:

b'\x80\x03]q\x00(X\x03\x00\x00\x00LSTq\x01X\x03\x00\x00\x00LGAq\x02X\x03\x00\x00\x00SFOq\x03X\x03\x00\x00\x00BOMq\x04X\x03\x00\x00\x00JFKq\x05X\x03\x00\x00\x00MIAq\x06e.'
 
import pickle
lst = ["LST", "LGA", "SFO", "BOM", "JFK", "MIA"]
x = pickle.dumps(lst)
print(pickle.loads(x))

Output:

['LST', 'LGA', 'SFO', 'BOM', 'JFK', 'MIA']