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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 equalspairs(X, Y):
 """ Indices of elements in a sorted numpy array equal to those in another. Given numpy array `X` and sorted numpy array `Y`, determine the indices in Y equal to indices in X. Returns `[A,B]` where `A` and `B` are numpy arrays of indices in `X` such that:: Y[A[i]:B[i]] = Y[Y == X[i]]` `A[i] = B[i] = 0` if `X[i]` is not in `Y`. **Parameters** **X** : numpy array Numpy array to compare to the sorted numpy array `Y`. **Y** : numpy array Sorted numpy array. Determine the indices of elements of `Y` equal to those in numpy array `X`. **Returns** **A** : numpy array List of indices in `Y`, `len(A) = len(Y)`. **B** : numpy array List of indices in `Y`, `len(B) = len(Y)`. **See Also:** :func:`tabular.fast.recarrayequalspairs` """

    T = Y.copy()
    R = (T[1:] != T[:-1]).nonzero()[0]
    R = np.append(R,np.array([len(T)-1]))
    M = R[R.searchsorted(range(len(T)))]
    D = T.searchsorted(X)
    T = np.append(T,np.array([0]))
    M = np.append(M,np.array([0]))
    A = (T[D] == X) * D
    B = (T[D] == X) * (M[D] + 1)
    return [A,B]