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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 _execCommand(Argv, collect_missing):

 r"""Worker of execCommand.
 """

  if not Argv:
    raise HandledException('Please specify a command!')

  RouteParts = Argv[0].split('/')
  Args, KwArgs = getDigestableArgs(Argv[1:])

  ResolvedMember = getDescendant(BaseGroup, RouteParts[:])

  if isinstance(ResolvedMember, Group):
    raise HandledException('Please specify a task.', Member=ResolvedMember)

  if not isinstance(ResolvedMember, Task):
    raise HandledException('No such task.', Member=BaseGroup)

  return ResolvedMember.__collect_n_call__(*Args, **KwArgs) if collect_missing else ResolvedMember(*Args, **KwArgs)