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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 VectorLen(self, off):
 """VectorLen retrieves the length of the vector whose offset is stored at "off" in this object."""

        N.enforce_number(off, N.UOffsetTFlags)

        off += self.Pos
        off += encode.Get(N.UOffsetTFlags.packer_type, self.Bytes, off)
        ret = encode.Get(N.UOffsetTFlags.packer_type, self.Bytes, off)
        return ret