__all__ = ["manual_am_modulation", "manual_conv1", "manual_conv2",
           "manual_hilbert", "manual_fourier1", "manual_fourier2",
           "manual_cos1", "manual_cos2", "manual_sin1", "manual_interp1",
           "manual_io1", "manual_io2", "manual_modulation",
           "manual_spectr"]
