def lower_first_char(string):
    """De-capitalize the first letter of a string.

    Args:
        string (str): The input string.

    Returns:
        str: The de-capitalized string.

    .. note::
        This function is not the exact opposite of the capitalize function of the
        standard library. For example, capitalize('abC') returns Abc rather than AbC.
    """
    if not string:  # Added to handle case where s == None
        return
    else:
        return string[0].lower() + string[1:]