def arg(match: kw(ast.arg, annotation=None)):
     return arg
 def assertstmt(match: kw(ast.Assert, msg=None)):
     yield 'assert %s' % ( MatchExpr(test) )
 def slice_end(match: kw(ast.Slice, lower=None)):
     result = ['', MatchExpr(upper)]
     if step is not None:
         result.append(MatchExpr(step))
     return ':'.join(result)
 def no_alias(match: kw(ast.alias, asname=None)):
     return name