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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 transform_from_rot_trans(R, t):
 """Transforation matrix from rotation matrix and translation vector."""

    R = R.reshape(3, 3)
    t = t.reshape(3, 1)
    return np.vstack((np.hstack([R, t]), [0, 0, 0, 1]))