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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_size(v):
 """ Returns the size of the vector. 3 3 3 3 3 Traceback (most recent call last):
 ValueError: Cannot treat an ndarray of shape (1, 3) as a vector """

    if isinstance(v, Vector):
        return len(v)
    elif type(v) in (array.array, list, tuple, xrange):
        return len(v)
    elif type(v) == np.ndarray:
        if v.ndim == 1 or (v.ndim == 2 and v.shape[1] == 1):
            return len(v)
        else:
            raise ValueError("Cannot treat an ndarray of shape %s as a vector" % str(v.shape))
    elif _have_scipy and scipy.sparse.issparse(v):
        assert v.shape[1] == 1, "Expected column vector"
        return v.shape[0]
    else:
        raise TypeError("Cannot treat type %s as a vector" % type(v))