def signal_to_noise_limit_tag_from_signal_to_noise_limit(signal_to_noise_limit):
    """Generate a signal to noise limit tag, to customize phase names based on limiting the signal to noise ratio of
    the dataset being fitted.

    This changes the phase name 'phase_name' as follows:

    signal_to_noise_limit = None -> phase_name
    signal_to_noise_limit = 2 -> phase_name_snr_2
    signal_to_noise_limit = 10 -> phase_name_snr_10
    """
    if signal_to_noise_limit is None:
        return ""
    else:
        return "__snr_" + str(signal_to_noise_limit)