如何创建并使用自定义函数在Python编程中？

def example_function(param1, param2):
    """
    This is an example function that takes two parameters and returns their sum.
    Parameters:
    param1 (int or float): The first parameter to add.
    param2 (int or float): The second parameter to add.
    Returns:
    int or float: The sum of the two parameters.
    """
    return param1 + param2
Example usage:
result = example_function(5, 3)
print("The sum is:", result)