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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 _vector_or_scalar(x, type='row'):
 """Convert an object to either a scalar or a row or column vector."""

    if isinstance(x, (list, tuple)):
        x = np.array(x)
    if isinstance(x, np.ndarray):
        assert x.ndim == 1
        if type == 'column':
            x = x[:, None]
    return x