def initialize(self, connection):
        try:
            self.server_version_info = \
                self._get_server_version_info(connection)
        except NotImplementedError:
            self.server_version_info = None
        try:
            self.default_schema_name = \
                self._get_default_schema_name(connection)
        except __HOLE__:
            self.default_schema_name = None

        try:
            self.default_isolation_level = \
                self.get_isolation_level(connection.connection)
        except NotImplementedError:
            self.default_isolation_level = None

        self.returns_unicode_strings = self._check_unicode_returns(connection)

        if self.description_encoding is not None and \
                self._check_unicode_description(connection):
            self._description_decoder = self.description_encoding = None

        self.do_rollback(connection.connection)
dataset/ETHPy150Open RoseOu/flasky/venv/lib/python2.7/site-packages/sqlalchemy/engine/default.py/DefaultDialect.initialize