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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 applyFilters(self, endpoint):
 """Apply filter functions to an endpoint until one of them returns non-None."""

        for filter_function in self.filter_functions:
            e = filter_function(endpoint)
            if e is not None:
                # Once one of the filters has returned an
                # endpoint, do not apply any more.
                return e

        return None