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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 Dir_anis_corr(InDir, AniSpec):
 """ takes the 6 element 's' vector and the Dec,Inc 'InDir' data, performs simple anisotropy correction. returns corrected Dec, Inc """

    Dir = np.zeros((3), 'f')
    Dir[0] = InDir[0]
    Dir[1] = InDir[1]
    Dir[2] = 1.
    chi, chi_inv = check_F(AniSpec)
    if chi[0][0] == 1.:
        return Dir  # isotropic
    X = dir2cart(Dir)
    M = np.array(X)
    H = np.dot(M, chi_inv)
    return cart2dir(H)