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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 process(self, tup):
 """Group non-tick Tuples into batches by ``group_key``. .. warning:: This method should **not** be overriden. If you want to tweak how Tuples are grouped into batches, override ``group_key``. """

        # Append latest Tuple to batches
        group_key = self.group_key(tup)
        self._batches[group_key].append(tup)