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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def domain(value, allow_empty = False, allow_ips = False, **kwargs):
 """Validate that ``value`` is a valid domain name. .. caution:: This validator does not verify that ``value`` **exists** as a domain. It merely verifies that its contents *might* exist as a domain. .. note:: This validator checks to validate that ``value`` resembles a valid domain name. It is - generally - compliant with `RFC 1035 <https://tools.ietf.org/html/rfc1035>`_ and `RFC 6761 <https://tools.ietf.org/html/rfc6761>`_, however it diverges in a number of key ways: * Including authentication (e.g. ``username:password@domain.dev``) will fail validation. * Including a path (e.g. ``domain.dev/path/to/file``) will fail validation. * Including a port (e.g. ``domain.dev:8080``) will fail validation. If you are hoping to validate a more complete URL, we recommend that you see :func:`url <validator_collection.validators.url>`. .. hint:: Leading and trailing whitespace will be automatically stripped. :param value: The value to validate. :type value: :class:`str <python:str>` / :obj:`None <python:None>` :param allow_empty: If ``True``, returns :obj:`None <python:None>` if ``value`` is empty. If ``False``, raises a :class:`EmptyValueError <validator_collection.errors.EmptyValueError>` if ``value`` is empty. Defaults to ``False``. :type allow_empty: :class:`bool <python:bool>` :param allow_ips: If ``True``, will succeed when validating IP addresses, If ``False``, will raise a :class:`InvalidDomainError` if ``value`` is an IP address. Defaults to ``False``. :type allow_ips: :class:`bool <python:bool>` :returns: ``value`` / :obj:`None <python:None>` :rtype: :class:`str <python:str>` / :obj:`None <python:None>` :raises EmptyValueError: if ``value`` is empty and ``allow_empty`` is ``False`` :raises CannotCoerceError: if ``value`` is not a :class:`str <python:str>` or :obj:`None <python:None>` :raises InvalidDomainError: if ``value`` is not a valid domain name or empty with ``allow_empty`` set to ``True`` :raises SlashInDomainError: if ``value`` contains a slash or backslash :raises AtInDomainError: if ``value`` contains an ``@`` symbol :raises ColonInDomainError: if ``value`` contains a ``:`` symbol :raises WhitespaceInDomainError: if ``value`` contains whitespace """

    is_recursive = kwargs.pop('is_recursive', False)

    if not value and not allow_empty:
        raise errors.EmptyValueError('value (%s) was empty' % value)
    elif not value:
        return None

    if not isinstance(value, basestring):
        raise errors.CannotCoerceError('value must be a valid string, '
                                       'was %s' % type(value))

    if '/' in value:
        raise errors.SlashInDomainError('valid domain name cannot contain "/"')
    if '\\' in value:
        raise errors.SlashInDomainError('valid domain name cannot contain "\\"')
    if '@' in value:
        raise errors.AtInDomainError('valid domain name cannot contain "@"')
    if ':' in value:
        raise errors.ColonInDomainError('valid domain name cannot contain ":"')

    value = value.strip().lower()

    for item in string_.whitespace:
        if item in value:
            raise errors.WhitespaceInDomainError('valid domain name cannot contain '
                                                 'whitespace')

    if value in SPECIAL_USE_DOMAIN_NAMES:
        return value

    if allow_ips:
        try:
            ip_address(value, allow_empty = allow_empty)
            is_valid = True
        except (ValueError, TypeError, AttributeError):
            is_valid = False

        if is_valid:
            return value

    is_valid = DOMAIN_REGEX.match(value)

    if not is_valid and not is_recursive:
        with_prefix = 'http://' + value
        try:
            url(with_prefix, force_run = True, is_recursive = True)                                  # pylint: disable=E1123
        except ValueError:
            raise errors.InvalidDomainError('value (%s) is not a valid domain' % value)

    return value