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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 _check_filter_specific_tag(self, specific_tag: list):
 """Check if specific_tag parameter is valid. :param list specific_tag: list of specific tag to check """

        if isinstance(specific_tag, list):
            if len(specific_tag) > 0:
                specific_tag = ",".join(specific_tag)
            else:
                specific_tag = ""
        else:
            raise TypeError("'specific_tag' expects a list")
        return specific_tag