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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 cut_segments(x2d, tr, start, stop):
 """Cut continuous signal into segments. Parameters x2d : array, shape (m, n) Input data with m signals and n samples. tr : list of int Trigger positions. start : int Window start (offset relative to trigger). stop : int Window end (offset relative to trigger). Returns ------- x3d : array, shape (len(tr), m, stop-start) Segments cut from data. Individual segments are stacked along the first dimension. See also -------- cat_trials : Concatenate segments. Examples -------- (3, 5, 50) """

    if start != int(start):
        raise ValueError("start index must be an integer")
    if stop != int(stop):
        raise ValueError("stop index must be an integer")

    x2d = np.atleast_2d(x2d)
    tr = np.asarray(tr, dtype=int).ravel()
    win = np.arange(start, stop, dtype=int)
    return np.concatenate([x2d[np.newaxis, :, t + win] for t in tr])