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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 is_transition_matrix(T, tol=1e-10):
 """ Tests whether T is a transition matrix Parameters T : ndarray shape=(n, n) matrix to test tol : float tolerance to check with Returns ------- Truth value : bool True, if all elements are in interval [0, 1] and each row of T sums up to 1. False, otherwise """

    if T.ndim != 2:
        return False
    if T.shape[0] != T.shape[1]:
        return False
    dim = T.shape[0]
    X = np.abs(T) - T
    x = np.sum(T, axis=1)
    return np.abs(x - np.ones(dim)).max() < dim * tol and X.max() < 2.0 * tol