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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 load_dialect_impl(self, dialect):
 # type: (DefaultDialect) -> TypeEngine """Select impl by dialect."""

        if self.__use_json(dialect):
            return dialect.type_descriptor(self.__json_type)
        return dialect.type_descriptor(sqlalchemy.UnicodeText)