#trouble.difficulty  a source of difficulty: "one trouble after another delayed the job"; "what's the problem?"
  supertype:  difficulty  a factor causing trouble in achieving a positive result or tending to produce a negative result; "serious difficulties were encountered in obtaining a pure reagent"
  subtype:  can_of_worms  (informal) a source of unpredictable trouble and complexity
  subtype:  deep_water  serious trouble
  subtype:  growing_pains__growingpain  problems that arise in enlarging an enterprise (especially in the early stages)
  subtype:  matter.trouble  a problem; "is anything the matter?"

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