def METHOD_NAME(label):
    '''
    Changes a label possibly containing a modifier such as "-" or "#" into
    a unicode string.
    >>> graph.utilities.accidentalLabelToUnicode('B-4')
    'B♭4'
    Since matplotlib's default fonts do not support double sharps or double flats,
    etc. these are converted as best we can...
    >>> graph.utilities.accidentalLabelToUnicode('B--4')
    'B♭♭4'
    '''
    if not isinstance(label, str):
        return label
    for modifier, unicodeAcc in pitch.unicodeFromModifier.items():
        if modifier != '' and modifier in label and modifier in ('-', '#'):
            # ideally eventually matplotlib will do the other accidentals...
            label = label.replace(modifier, unicodeAcc)
            break
    return label