def process_iter():
 def add(pid):
  proc = Process(pid)
  _pmap[proc.pid] = proc
  return proc
 def remove(pid):
  _pmap.pop(pid, None)
 a = set(pids())
 b = set(_pmap.keys())
 new_pids = (a - b)
 gone_pids = (b - a)
 for pid in gone_pids:
  remove(pid)
 for (pid, proc) in sorted((list(_pmap.items()) + list(dict.fromkeys(new_pids).items()))):
  try:
   if (proc is None):
    (yield add(pid))
   elif proc.is_running():
    (yield proc)
   else:
    (yield add(pid))
  except NoSuchProcess:
   remove(pid)
  except AccessDenied:
   if ((proc is None) and (pid in _pmap)):
    try:
     (yield _pmap[pid])
    except KeyError:
     pass
   else:
    raise

def process_iter ( ) : def add ( pid ) : proc = Process ( pid ) _pmap [ proc . pid ] = proc return proc def remove ( pid ) : _pmap . pop ( pid , None ) a = set ( pids ( ) ) b = set ( _pmap . keys ( ) ) new_pids = ( a - b ) gone_pids = ( b - a ) for pid in gone_pids : remove ( pid ) for ( pid , proc ) in sorted ( ( list ( _pmap . items ( ) ) + list ( dict . fromkeys ( new_pids ) . items ( ) ) ) ) : try : if ( proc is None ) : ( yield add ( pid ) ) elif proc . is_running ( ) : ( yield proc ) else : ( yield add ( pid ) ) except NoSuchProcess : remove ( pid ) except AccessDenied : if ( ( proc is None ) and ( pid in _pmap ) ) : try : ( yield _pmap [ pid ] ) except KeyError : pass else : raise
return a generator yielding a process instance for all running processes .