def get_service_account_credentials(self):
        # Bug fix for https://github.com/pydata/pandas/issues/12572
        # We need to know that a supported version of oauth2client is installed
        # Test that either of the following is installed:
        # - SignedJwtAssertionCredentials from oauth2client.client
        # - ServiceAccountCredentials from oauth2client.service_account
        # SignedJwtAssertionCredentials is available in oauthclient < 2.0.0
        # ServiceAccountCredentials is available in oauthclient >= 2.0.0
        oauth2client_v1 = True
        oauth2client_v2 = True

        try:
            from oauth2client.client import SignedJwtAssertionCredentials
        except __HOLE__:
            oauth2client_v1 = False

        try:
            from oauth2client.service_account import ServiceAccountCredentials
        except ImportError:
            oauth2client_v2 = False

        if not oauth2client_v1 and not oauth2client_v2:
            raise ImportError("Missing oauth2client required for BigQuery "
                              "service account support")

        from os.path import isfile

        try:
            if isfile(self.private_key):
                with open(self.private_key) as f:
                    json_key = json.loads(f.read())
            else:
                # ugly hack: 'private_key' field has new lines inside,
                # they break json parser, but we need to preserve them
                json_key = json.loads(self.private_key.replace('\n', '   '))
                json_key['private_key'] = json_key['private_key'].replace(
                    '   ', '\n')

            if compat.PY3:
                json_key['private_key'] = bytes(
                    json_key['private_key'], 'UTF-8')

            if oauth2client_v1:
                return SignedJwtAssertionCredentials(
                    json_key['client_email'],
                    json_key['private_key'],
                    self.scope,
                )
            else:
                return ServiceAccountCredentials.from_json_keyfile_dict(
                    json_key,
                    self.scope)
        except (KeyError, ValueError, TypeError, AttributeError):
            raise InvalidPrivateKeyFormat(
                "Private key is missing or invalid. It should be service "
                "account private key JSON (file path or string contents) "
                "with at least two keys: 'client_email' and 'private_key'. "
                "Can be obtained from: https://console.developers.google."
                "com/permissions/serviceaccounts")
dataset/ETHPy150Open pydata/pandas/pandas/io/gbq.py/GbqConnector.get_service_account_credentials