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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 set_windows_env_var(key, value):
 """Set an env var. Raises: WindowsError """


    if not isinstance(key, text_type):
        raise TypeError("%r not of type %r" % (key, text_type))

    if not isinstance(value, text_type):
        raise TypeError("%r not of type %r" % (value, text_type))

    status = winapi.SetEnvironmentVariableW(key, value)
    if status == 0:
        raise ctypes.WinError()