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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_to_2d(t):
 """Convert vectors to column matrices, to always have a 2d shape."""

    t = np.asarray(t)

    dim = len(t.shape)
    assert dim <= 2

    if dim < 2:
        t = np.atleast_2d(t).T

    return t