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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 _sortValue_isMonospace(font):
 """ Returns 0 if the font is monospace. Returns 1 if the font is not monospace. """

    if font.info.postscriptIsFixedPitch:
        return 0
    if not len(font):
        return 1
    testWidth = None
    for glyph in font:
        if testWidth is None:
            testWidth = glyph.width
        else:
            if testWidth != glyph.width:
                return 1
    return 0