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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 subentity(self, Entity, index):
 """Return child entity"""

        dim = Entity.__dimension__
        entity = Entity.empty()
        
        if index >= self.dimensions[dim]:
            raise ValueError('index {} out of bounds for dimension {} (size {})'
                             .format(index, dim, self.dimensions[dim]))
        
        
        for name, attr in self.__attributes__.items():
            if attr.dim == dim:
                # If the dimension of the attributes is the same of the
                # dimension of the entity, we generate a field
                entity.__fields__[name] = attr.field(index)
            elif attr.dim in entity.dimensions:
                # Special case, we don't need to do anything
                if self.dimensions[attr.dim] == 0:
                    continue

                # Else, we generate a subattribute
                mapped_index = self.maps[attr.dim, dim].value == index
                entity.__attributes__[name] = attr.sub(mapped_index)
                entity.dimensions[attr.dim] = np.count_nonzero(mapped_index)

        for name, rel in self.__relations__.items():
            if rel.map == dim:
                # The relation is between entities we need to return
                # which means the entity doesn't know about that
                pass
            if rel.map in entity.dimensions:
                # Special case, we don't need to do anything
                if self.dimensions[rel.dim] == 0:
                    continue
                mapped_index = self.maps[rel.dim, dim].value == index
                entity.__relations__[name] = rel.sub(mapped_index)
                entity.dimensions[rel.dim] = np.count_nonzero(mapped_index)
                
                # We need to remap values
                convert_index = self.maps[rel.map, dim].value == index
                entity.__relations__[name].remap(convert_index.nonzero()[0],
                                                 range(entity.dimensions[rel.map]))
        
        return entity