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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 appdata_roaming_dir():
 """Returns the roaming AppData directory for the installed ArcGIS Desktop."""

    install = arcpy.GetInstallInfo('desktop')
    app_data = arcpy.GetSystemEnvironment("APPDATA")
    product_dir = ''.join((install['ProductName'], major_version()))
    return os.path.join(app_data, 'ESRI', product_dir)