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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 serve_get(self, path, **params):
 """ Find a GET callback for the given HTTP path, call it and return the results. The callback is called with two arguments, the path used to match it, and params which include the BaseHTTPRequestHandler instance. The callback must return a tuple: (code, content, content_type) If multiple registrations match the path, the one with the longest matching text will be used. Matches are always anchored at the start of the path. None is returned if no registered callback is willing to handle a path. """

        if path is None: return None

        matched = self._match_path(path, self.get_registrations)
        if matched is None:
            return None
        else:
            return matched(path, **params)