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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 restrict_bond_dict(self, bond_dict):
 """Restrict a bond dictionary to self. Args: bond_dict (dict):
 Look into :meth:`~chemcoord.Cartesian.get_bonds`, to see examples for a bond_dict. Returns: bond dictionary """

        return {j: bond_dict[j] & set(self.index) for j in self.index}