# Python: Find the value of the first element in the given list that satisfies the provided testing function

## Python List: Exercise - 239 with Solution

Write a Python program to find the value of the first element in the given list that satisfies the provided testing function.

Use a list comprehension and next() to return the first element in lst for which fn returns True.

**Sample Solution:**

**Python Code:**

```
# Define a function 'find' that takes a list 'lst' and a function 'fn' as input.
def find(lst, fn):
# Use a generator expression to find the first element 'x' in the list 'lst' for which 'fn(x)' is true.
# The 'next' function is used to retrieve the first matching element.
return next(x for x in lst if fn(x))
# Call the 'find' function with a list and a lambda function to find the first odd number in the list.
# Print the result.
print(find([1, 2, 3, 4], lambda n: n % 2 == 1))
# Call the 'find' function again with a lambda function to find the first even number in the list.
# Print the result.
print(find([1, 2, 3, 4], lambda n: n % 2 == 0))
```

Sample Output:

1 2

**Flowchart:**

**Python Code Editor:**

**Previous:** Write a Python program to calculate the average of a given list, after mapping each element to a value using the provided function.

**Next:** Write a Python program to find the value of the last element in the given list that satisfies the provided testing function.

**What is the difficulty level of this exercise?**

Test your Programming skills with w3resource's quiz.

**Weekly Trends and Language Statistics**- Weekly Trends and Language Statistics