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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 get_transaction(cls, txid):
 """Gets the full transaction details. :param txid: The transaction id in question. :type txid: ``str`` :raises ConnectionError: If all API services fail. :rtype: ``Transaction`` """


        for api_call in cls.GET_TX_MAIN:
            try:
                return api_call(txid)
            except cls.IGNORED_ERRORS:
                pass

        raise ConnectionError('All APIs are unreachable.')