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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 _initialize(self, chain, length):
 """Prepare for tallying. Create a new chain."""

        # If this db was loaded from the disk, it may not have its
        # tallied step methods' getfuncs yet.
        if self._getfunc is None:
            self._getfunc = self.db.model._funs_to_tally[self.name]