def unquote(input_str):
    """
    Unquote a string. Removes one set of leading quotes (' or ")

    :param input_str: Input string
    :type input_str: ```Optional[str]```

    :returns: Unquoted string
    :rtype: ```Optional[str]```
    """
    if (
        isinstance(input_str, str)
        and len(input_str) > 1
        and (
            input_str.startswith('"')
            and input_str.endswith('"')
            or input_str.startswith("'")
            and input_str.endswith("'")
        )
    ):
        return input_str[1:-1]
    return input_str