def initialize(self, connection):
        super(PGDialect, self).initialize(connection)
        self.implicit_returning = (8, 2) > self.server_version_info and \
            self.__dict__.get('implicit_returning', True)
        self.supports_native_enum = self.server_version_info >= (8, 3)
        if not self.supports_native_enum:
            self.colspecs = self.colspecs.copy()
            # pop base Enum type
            self.colspecs.pop(sqltypes.Enum, None)
            # psycopg2, others may have placed ENUM here as well
            self.colspecs.pop(ENUM, None)

        # http://www.postgresql.org/docs/9.3/static/release-9-2.html#AEN116689
        self.supports_smallserial = self.server_version_info >= (9, 2)

        self._backslash_escapes = self.server_version_info < (8, 2) or \
            connection.scalar(
            "show standard_conforming_strings"
        ) == 'off'
dataset/ETHPy150Open RoseOu/flasky/venv/lib/python2.7/site-packages/sqlalchemy/dialects/postgresql/base.py/PGDialect.initialize/swapped operands of `>`