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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 get_tilt(cont):
 """Compute tilt of raw contour relative to channel axis Parameters cont: ndarray or list of ndarrays of shape (N,2) A 2D array that holds the contour of an event (in pixels) e.g. obtained using `mm.contour` where `mm` is an instance of `RTDCBase`. The first and second columns of `cont` correspond to the x- and y-coordinates of the contour. Returns ------- tilt: float or ndarray of size N Tilt of the contour in the interval [0, PI/2] References - `<https://en.wikipedia.org/wiki/Image_moment#Examples_2>`__ """

    if isinstance(cont, np.ndarray):
        # If cont is an array, it is not a list of contours,
        # because contours can have different lengths.
        cont = [cont]
        ret_list = False
    else:
        ret_list = True

    length = len(cont)

    tilt = np.zeros(length, dtype=float) * np.nan

    for ii in range(length):
        moments = cont_moments_cv(cont[ii])
        if moments is not None:
            # orientation of the contour
            oii = 0.5 * np.arctan2(2 * moments['mu11'],
                                   moments['mu02'] - moments['mu20'])
            # +PI/2 because relative to channel axis
            tilt[ii] = oii + np.pi/2

    # restrict to interval [0,PI/2]
    tilt = np.mod(tilt, np.pi)
    tilt[tilt > np.pi/2] -= np.pi
    tilt = np.abs(tilt)

    if not ret_list:
        tilt = tilt[0]

    return tilt