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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 _generate_identifier_name(self, columns, prefix="", max_size=30):
 """ Generates an identifier from a list of column names obeying a certain string length. """

        hash = ""
        for column in columns:
            hash += "%x" % binascii.crc32(encode(str(column)))

        return (prefix + "_" + hash)[:max_size]