regexp spec

Would this be a good way to define a regexp (dulcinea) ?

mario

class regexp(SpecOperator):

     def __init__(self, pattern='^[-A-Za-z0-9_@.]*$'):
         import re
         self.re = re.compile(pattern)
         self.args =  (self.re,)

     def __call__(self, value):
         try:
             if self.re.match(value):
                 return True
             return False
         except TypeError:
             return False

     def __str__(self):
         return "string matching pattern '%s'" % (self.re.pattern)