What is Python Function Signature

In Python, a function signature refers to the declaration and definition of a function, which includes its name, parameters, and return type (if any). The function signature helps define the function’s interface, allowing other parts of the code to call the function correctly.

The basic syntax of a function signature is as follows:

def function_name(parameter1, parameter2, ...):
    # Function body
    # ...
    return return_value  # (optional, not required for all functions)

Explanation of components in the function signature:

  • def: It is the keyword used to define a function in Python.
  • function_name: This is the identifier that you choose to name the function. It should follow the rules for naming identifiers in Python.
  • parameter1, parameter2, ...: These are the input parameters or arguments that the function takes. You can have any number of parameters or none at all.
  • return_value: This is the value that the function returns to the caller. It is optional and depends on whether the function needs to return a result.

Here’s an example of a simple function signature:

def add_numbers(a, b):
    return a + b

In this example, the function name is add_numbers, and it takes two parameters a and b. It returns the sum of a and b.

It’s important to note that Python is a dynamically typed language, so you don’t need to specify the data types of the parameters or the return value in the function signature. The data types are determined at runtime based on the actual arguments and the function’s behavior.


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