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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 pop(self, count):
 """Returns new context stack, which doesn't contain few levels """

        if len(self._contexts) - 1 < count:
            _logger.error("#pop value is too big %d", len(self._contexts))
            if len(self._contexts) > 1:
                return ContextStack(self._contexts[:1], self._data[:1])
            else:
                return self

        return ContextStack(self._contexts[:-count], self._data[:-count])