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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 arduino_default_path():
 """platform specific default root path."""

    if sys.platform == 'darwin':
        s = path('/Applications/Arduino.app/Contents/Resources/Java')
    elif sys.platform == 'win32':
        s = None
    else:
        s = path('/usr/share/arduino/')
    return s