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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 url(self, pattern, method=None, name=None):
 """Decorator to map url pattern to the callable. Args: pattern (:obj:`str`):
 URL pattern to add. This is usually '/' separated path. Parts of the URL can be parameterised using curly braces. Examples: "/", "/path/to/resource", "/resoures/{param}" method (:obj:`str`, :obj:`list` of :obj:`str`, optional):
 HTTP methods for the path specied. By default, GET method is added. Value can be either a single method, by passing a string, or multiple methods, by passing a list of strings. name (:obj:`str`):
 Name for the pattern that can be used for reverse matching Note: A trailing '/' is always assumed in the pattern. Example: See Also: :func:`drongo.managers.url.UrlManager.add` """

        def _inner(call):
            self._url_manager.add(pattern, method, call, name)
            return call
        return _inner