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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 L_fc(fdata):
 """Apply L in the Fourier domain."""


    fd = np.copy(fdata)

    dphi_fc(fdata)
    divsin_fc(fdata)

    dtheta_fc(fd)

    return (1j * fdata, -1j * fd)