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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_ufo_font_attributes(self, family_name):
 """Generate a list of UFOs with metadata loaded from .glyphs data. Modifies the list of UFOs in the UFOBuilder (self) in-place. """


    font = self.font

    # "date" can be missing; Glyphs.app removes it on saving if it's empty:
    # https://github.com/googlei18n/glyphsLib/issues/134
    date_created = getattr(font, "date", None)
    if date_created is not None:
        date_created = to_ufo_time(date_created)
    units_per_em = font.upm
    version_major = font.versionMajor
    version_minor = font.versionMinor
    copyright = font.copyright
    designer = font.designer
    designer_url = font.designerURL
    manufacturer = font.manufacturer
    manufacturer_url = font.manufacturerURL
    # XXX note is unused?
    # note = font.note
    glyph_order = list(glyph.name for glyph in font.glyphs)

    for index, master in enumerate(font.masters):
        source = self._designspace.newSourceDescriptor()
        ufo = self.ufo_module.Font()
        source.font = ufo

        ufo.lib[APP_VERSION_LIB_KEY] = font.appVersion
        ufo.lib[KEYBOARD_INCREMENT_KEY] = font.keyboardIncrement

        if date_created is not None:
            ufo.info.openTypeHeadCreated = date_created
        ufo.info.unitsPerEm = units_per_em
        ufo.info.versionMajor = version_major
        ufo.info.versionMinor = version_minor

        if copyright:
            ufo.info.copyright = copyright
        if designer:
            ufo.info.openTypeNameDesigner = designer
        if designer_url:
            ufo.info.openTypeNameDesignerURL = designer_url
        if manufacturer:
            ufo.info.openTypeNameManufacturer = manufacturer
        if manufacturer_url:
            ufo.info.openTypeNameManufacturerURL = manufacturer_url

        ufo.glyphOrder = glyph_order

        self.to_ufo_names(ufo, master, family_name)
        self.to_ufo_family_user_data(ufo)
        self.to_ufo_custom_params(ufo, font)

        self.to_ufo_master_attributes(source, master)

        ufo.lib[MASTER_ORDER_LIB_KEY] = index
        # FIXME: (jany) in the future, yield this UFO (for memory, lazy iter)
        self._designspace.addSource(source)
        self._sources[master.id] = source