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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 stft_from_frames(frames, window='hann', dtype=np.complex64):
 """ Variation of the librosa.core.stft function, that computes the short-time-fourier-transfrom from frames instead from the signal. See http://librosa.github.io/librosa/_modules/librosa/core/spectrum.html#stft """


    win_length = frames.shape[0]
    n_fft = win_length

    fft_window = filters.get_window(window, win_length, fftbins=True)

    # Reshape so that the window can be broadcast
    fft_window = fft_window.reshape((-1, 1))

    # Pre-allocate the STFT matrix
    stft_matrix = np.empty((int(1 + n_fft // 2), frames.shape[1]),
                           dtype=dtype,
                           order='F')

    # how many columns can we fit within MAX_MEM_BLOCK?
    n_columns = int(util.MAX_MEM_BLOCK / (stft_matrix.shape[0] *
                                          stft_matrix.itemsize))

    for bl_s in range(0, stft_matrix.shape[1], n_columns):
        bl_t = min(bl_s + n_columns, stft_matrix.shape[1])

        # RFFT and Conjugate here to match phase from DPWE code
        stft_matrix[:, bl_s:bl_t] = fft.fft(fft_window *
                                            frames[:, bl_s:bl_t],
                                            axis=0)[:stft_matrix.shape[0]].conj()

    return stft_matrix