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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 _validate_tag_key(self, tag_key, exception_param='tags.X.member.key'):
 """Validates the tag key. :param all_tags: Dict to check if there is a duplicate tag. :param tag_key: The tag key to check against. :param exception_param: The exception parameter to send over to help format the message. This is to reflect the difference between the tag and untag APIs. :return: """

        # Validate that the key length is correct:
        if len(tag_key) > 128:
            raise TagKeyTooBig(tag_key, param=exception_param)

        # Validate that the tag key fits the proper Regex:
        # [\w\s_.:/=+\-@]+ SHOULD be the same as the Java regex on the AWS documentation: [\p{L}\p{Z}\p{N}_.:/=+\-@]+
        match = re.findall(r'[\w\s_.:/=+\-@]+', tag_key)
        # Kudos if you can come up with a better way of doing a global search :)
        if not len(match) or len(match[0]) < len(tag_key):
            raise InvalidTagCharacters(tag_key, param=exception_param)