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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 iter_surrounding(self, center_key):
 """Iterate over all bins surrounding the given bin"""

        for shift in self.neighbor_indexes:
            key = tuple(np.add(center_key, shift).astype(int))
            if self.integer_cell is not None:
                key = self.wrap_key(key)
            bin = self._bins.get(key)
            if bin is not None:
                yield key, bin