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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 to_glyphs_font_attributes(self, source, master, is_initial):
 """ Copy font attributes from `ufo` either to `self.font` or to `master`. Arguments: self -- The UFOBuilder ufo -- The current UFO being read master -- The current master being written is_initial -- True iff this the first UFO that we process """

    if is_initial:
        _set_glyphs_font_attributes(self, source)
    else:
        _compare_and_merge_glyphs_font_attributes(self, source)