Python: Check if a function is a user-defined function or not

Last update on April 24 2025 12:45:16 (UTC/GMT +8 hours)

1. User-Defined Function Checker

Write a Python program to check if a function is a user-defined function or not. Use types.FunctionType, types.LambdaType()

Sample Solution:

Python Code:

import types
def func(): 
    return 1

print(isinstance(func, types.FunctionType))
print(isinstance(func, types.LambdaType))
print(isinstance(lambda x: x, types.FunctionType))
print(isinstance(lambda x: x, types.LambdaType))
print(isinstance(max, types.FunctionType))
print(isinstance(max, types.LambdaType))
print(isinstance(abs, types.FunctionType))
print(isinstance(abs, types.LambdaType))

Sample Output:

True
True
True
True
False
False
False
False

Flowchart:

For more Practice: Solve these Related Problems:

Write a Python program that accepts a function as input and uses types.FunctionType and types.LambdaType to determine if it is user-defined, then prints the result.
Write a Python script to iterate over a list containing a built-in function, a lambda, and a user-defined function, and print which ones are user-defined.
Write a Python function that distinguishes between a lambda and a regular user-defined function using types.FunctionType and types.LambdaType, outputting specific messages for each case.
Write a Python program to define several functions (including nested functions) and use the types module to check and print whether each function is user-defined.

Go to:

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Python Code Editor:

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