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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 sa_indices(num_states, num_actions):
 """ Generate `s_indices` and `a_indices` for `DiscreteDP`, for the case where all the actions are feasible at every state. Parameters num_states : scalar(int) Number of states. num_actions : scalar(int) Number of actions. Returns ------- s_indices : ndarray(int, ndim=1) Array containing the state indices. a_indices : ndarray(int, ndim=1) Array containing the action indices. Examples -------- array([0, 0, 0, 1, 1, 1, 2, 2, 2, 3, 3, 3]) array([0, 1, 2, 0, 1, 2, 0, 1, 2, 0, 1, 2]) """

    L = num_states * num_actions
    dtype = np.int_
    s_indices = np.empty(L, dtype=dtype)
    a_indices = np.empty(L, dtype=dtype)

    i = 0
    for s in range(num_states):
        for a in range(num_actions):
            s_indices[i] = s
            a_indices[i] = a
            i += 1

    return s_indices, a_indices