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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 _groupFontByFamily(self, font_files):
 """ Returns font files grouped in dict by font family. """

        font_families = defaultdict(list)
        for font_file in font_files:
            font = fc.FcFont(font_file)
            font_families[font.family[0][1]].append(font_file)
        return font_families