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Python: Find the indexes of all None items in a given list

Python List: Exercise - 202 with Solution

Write a Python program to find the indexes of all None items in a given list.

Sample Solution:

Python Code:

def relative_order(lst):
    result = [i for i in range(len(lst)) if lst[i] == None]
    return result

nums = [1, None, 5, 4,None, 0, None, None]
print("Original list:")
print(nums)
print("\nIndexes of all None items of the list:")
print(relative_order(nums))

Sample Output: 

Original list:
[1, None, 5, 4, None, 0, None, None]

Indexes of all None items of the list:
[1, 4, 6, 7]

Pictorial Presentation:

Python List: Find the indexes of all None items in a given list.

Flowchart:

Flowchart: Find the indexes of all None items in a given list.

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Python: Tips of the Day

Given a predicate function, fn, and a prop string, this curried function will then take an object to inspect by calling the property and passing it to the predicate:

Example:

def tips_check_prop(fn, prop):
  return lambda obj: fn(obj[prop])
check_age = tips_check_prop(lambda x: x >= 25, 'age')
user = {'name': 'Owen', 'age': 25}

print(check_age(user))

Output:

True

 

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