util.py 文件源码

def is_valid_cidr(cidr):
    """Verifies that a string is valid IPv4 or IPv6 CIDR specification.

    A cleaned up version of the CIDR string is returned if it is verified,
    otherwise a false value is returned.

    Uses the IPy library to verify addresses.
    """
    if (isinstance(cidr, six.string_types) and
            not cidr.isdigit() and '/' in cidr):
        try:
            valid_cidr = IPy.IP(cidr) is not None
        except (ValueError, TypeError):
            return False
        else:
            return valid_cidr
    return False