<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def match(self, string):
 """Match a string against the template. If the string matches the template, return a dict mapping template parameter names to converted values, otherwise return ``None``. {'name': 'David'} """

        m = self.regex.match(string)
        if m:
            c = self.type_converters
            return dict((k, c[k](v) if k in c else v)
                        for k, v in m.groupdict().iteritems())
        return None