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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 get_trans(self, out_vec=None):
 """Return the translation portion of the matrix as a vector. If out_vec is provided, store in out_vec instead of creating a new Vec3. """


        if out_vec:
            return out_vec.set(*self.data[3][:3])

        return Vec3(*self.data[3][:3])