def read(self, name):
        """Read migration from file."""
        call_params = dict()
        if os.name == 'nt' and sys.version_info >= (3, 0):
            # if system is windows - force utf-8 encoding
            call_params['encoding'] = 'utf-8'
        with open(os.path.join(self.migrate_dir, name + '.py'), **call_params) as f:
            code = f.read()
            scope = {}
            exec_in(code, scope)
            return scope.get('migrate', VOID), scope.get('rollback', VOID)
Read migration from file.