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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 sheardec2D(X, shearletsystem):
 """Shearlet Decomposition function."""

    coeffs = np.zeros(shearletsystem.shearlets.shape, dtype=complex)
    Xfreq = fftshift(fft2(ifftshift(X)))
    for i in range(shearletsystem.nShearlets):
        coeffs[:, :, i] = fftshift(ifft2(ifftshift(Xfreq * np.conj(
                                   shearletsystem.shearlets[:, :, i]))))
    return coeffs.real