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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 uninstall_packages():
 """ Uninstall unwanted packages """

    p = server_state('packages_installed')
    if p: installed = set(p)
    else: return
    env.uninstalled_packages[env.host] = []
    #first uninstall any that have been taken off the list
    packages = set(get_packages())
    uninstall = installed - packages
    if uninstall and env.verbosity:
        print env.host,'UNINSTALLING HOST PACKAGES'
    for p in uninstall:
        if env.verbosity:
            print ' - uninstalling',p
        uninstall_package(p)
        env.uninstalled_packages[env.host].append(p)
    set_server_state('packages_installed',get_packages())
    return