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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 synchronizer_class(self):
 """ returns synchronizer class """

        if not self.synchronizer_path or self.synchronizer_path == 'None' or not self.layer:
            return False
        # ensure data is up to date
        if (self._synchronizer_class is not None and self._synchronizer_class.__name__ not in self.synchronizer_path):
            self._synchronizer = None
            self._synchronizer_class = None
        # import synchronizer class only if not imported already
        if not self._synchronizer_class:
            self._synchronizer_class = import_by_path(self.synchronizer_path)
        return self._synchronizer_class