def my_function(a, b=2):
    """
    This function ...

    Parameters
    ----------
    a : float
        First operand.
    b : float, optional
        Second operand. The default is 2.

    Returns
    -------
    Sum of operands.

    Example
    -------
    >>> my_function(3)
    5
    """
    # Add a with b (this is a comment)
    return a + b