Concat a map. You can also optionally slice the operand map
        and apply an offset to each position before concatting

def concat(self, operand, start=0, end=0, offset=0):
        """Concat a map. You can also optionally slice the operand map
        and apply an offset to each position before concatting"""
        if not Gauged.map_concat(self.ptr, operand.ptr, start, end, offset):
            raise MemoryError