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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 filter(self, func):
 # type: (Callable[[BaseCollection], bool]) -> _CollectionGroupBy """Filter out Groups based on filtering function. The function should get a FeatureCollection and return True to leave in the Group and False to take it out. """

        results = OrderedDict()  # type: OrderedDict
        for name, group in self:
            if func(group):
                results[name] = group

        return self.__class__(results)