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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 create_aeff(event_class, event_type, egy, cth):
 """Create an array of effective areas versus energy and incidence angle. Binning in energy and incidence angle is controlled with the egy and cth input parameters. Parameters event_class : str Event class string (e.g. P8R2_SOURCE_V6). event_type : list egy : array_like Evaluation points in energy (MeV). cth : array_like Evaluation points in cosine of the incidence angle. """

    irf = create_irf(event_class, event_type)
    irf.aeff().setPhiDependence(False)
    theta = np.degrees(np.arccos(cth))

    # Exposure Matrix
    # Dimensions are Etrue and incidence angle
    m = np.zeros((len(egy), len(cth)))

    for i, x in enumerate(egy):
        for j, y in enumerate(theta):
            m[i, j] = irf.aeff().value(x, y, 0.0)

    return m