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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_plot_dims(signal, ann_samp):
    "Figure out the number of plot channels"
    if signal is not None:
        if signal.ndim == 1:
            sig_len = len(signal)
            n_sig = 1
        else:
            sig_len = signal.shape[0]
            n_sig = signal.shape[1]
    else:
        sig_len = 0
        n_sig = 0

    if ann_samp is not None:
        n_annot = len(ann_samp)
    else:
        n_annot = 0

    return sig_len, n_sig, n_annot, max(n_sig, n_annot)