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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 complete_modules(text):
    '''complete mavproxy module names'''
    import MAVProxy.modules, pkgutil
    modlist = [x[1] for x in pkgutil.iter_modules(MAVProxy.modules.__path__)]
    ret = []
    loaded = set(complete_loadedmodules(''))
    for m in modlist:
        if not m.startswith("mavproxy_"):
            continue
        name = m[9:]
        if not name in loaded:
            ret.append(name)
    return ret