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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 insert(self, index, *parts):
 """Return a copy with ``parts`` inserted before ``index``. The given partitions are inserted (as a block) into ``self``, yielding a new partition whose number of dimensions is the sum of the numbers of dimensions of all involved partitions. Note that no changes are made in-place. Parameters index : int Index of the dimension before which ``other`` is to be inserted. Negative indices count backwards from ``self.ndim``. Partitions to be inserted into ``self``. Returns ------- newpart : `RectPartition` The enlarged partition. Examples -------- uniform_partition([ 0., 0., -1.], [ 1., 1., 2.], (3, 5, 3)) See Also -------- append """

        if not all(isinstance(p, RectPartition) for p in parts):
            raise TypeError('`parts` must all be `RectPartition` instances, '
                            'got ({})'
                            ''.format(', '.join(repr(p) for p in parts)))

        newgrid = self.grid.insert(index, *(p.grid for p in parts))
        newset = self.set.insert(index, *(p.set for p in parts))
        return RectPartition(newset, newgrid)