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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 load_parent_implems(self, parent_implems):
 """Import previously defined implementations. Args: parent_implems (ImplementationList):
 List of implementations defined in a parent class. """

        for trname, attr, implem in parent_implems.get_custom_implementations():
            self.implementations[trname] = implem.copy()
            self.transitions_at[trname] = attr
            self.custom_implems.add(trname)