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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_master_user_data(self, ufo, master):
 """Set the GSFontMaster userData from the UFO master-specific lib data."""

    target_user_data = master.userData
    for key, value in ufo.lib.items():
        if _user_data_has_no_special_meaning(key):
            target_user_data[key] = value

    # Save UFO data files
    if ufo.data.fileNames:
        from glyphsLib.types import BinaryData

        ufo_data = {}
        for os_filename in ufo.data.fileNames:
            filename = posixpath.join(*os_filename.split(os.path.sep))
            ufo_data[filename] = BinaryData(ufo.data[os_filename])
        master.userData[UFO_DATA_KEY] = ufo_data