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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 neighborhood(self, elements: List[ELEMENT_NAME]) \ -> References: """ Return a list of all slots, classes and types that touch any element in elements, including the element itself @param elements: Elements to do proximity with @return: All slots and classes that touch element """

        touches = References()
        for element in elements:
            if element in self.schema.classes:
                touches.classrefs.add(element)
                if None in touches.classrefs:
                    raise ValueError("1")
                cls = self.schema.classes[element]
                if cls.is_a:
                    touches.classrefs.add(cls.is_a)
                if None in touches.classrefs:
                    raise ValueError("1")
                # Mixins include apply_to's
                touches.classrefs.update(set(cls.mixins))
                for slotname in cls.slots:
                    slot = self.schema.slots[slotname]
                    if slot.range in self.schema.classes:
                        touches.classrefs.add(slot.range)
                    elif slot.range in self.schema.types:
                        touches.typerefs.add(slot.range)
                    if None in touches.classrefs:
                        raise ValueError("1")
                if element in self.synopsis.rangerefs:
                    for slotname in self.synopsis.rangerefs[element]:
                        touches.slotrefs.add(slotname)
                        if self.schema.slots[slotname].domain:
                            touches.classrefs.add(self.schema.slots[slotname].domain)
            elif element in self.schema.slots:
                touches.slotrefs.add(element)
                slot = self.schema.slots[element]
                touches.slotrefs.update(set(slot.mixins))
                if slot.is_a:
                    touches.slotrefs.add(slot.is_a)
                if element in self.synopsis.inverses:
                    touches.slotrefs.update(self.synopsis.inverses[element])
                if slot.domain:
                    touches.classrefs.add(slot.domain)
                if slot.range in self.schema.classes:
                    touches.classrefs.add(slot.range)
                elif slot.range in self.schema.types:
                    touches.typerefs.add(slot.range)
            elif element in self.schema.types:
                if element in self.synopsis.rangerefs:
                    touches.slotrefs.update(self.synopsis.rangerefs[element])

        return touches