code: def clone(self):
      new_agenda = Agenda()
      set_list = [s.copy() for s in self.sets]
  
      new_allExs = set()
      for allEx, _ in set_list[Categories.ALL]:
          new_allEx = AllExpression(allEx.variable, allEx.term)
          try:
              new_allEx._used_vars = {used for used in allEx._used_vars}
          except AttributeError:
              new_allEx._used_vars = set()
          new_allExs.add((new_allEx, None))
      set_list[Categories.ALL] = new_allExs
  
      set_list[Categories.N_EQ] = {
          (NegatedExpression(n_eq.term), ctx)
          for (n_eq, ctx) in set_list[Categories.N_EQ]
      }
  
      new_agenda.sets = tuple(set_list)
      return new_agenda
  
imports: from nltk.inference.api import BaseProverCommand, Prover
  from nltk.internals import Counter
  from nltk.sem.logic import AbstractVariableExpression, AllExpression, AndExpression, ApplicationExpression, EqualityExpression, ExistsExpression, Expression, FunctionVariableExpression, IffExpression, ImpExpression, LambdaExpression, NegatedExpression, OrExpression, Variable, VariableExpression, unique_variable
label_desc: Use image node_id 2 for calling the Agenda obj's underlying member method code with example usage: obj.clone() and returns: new_agenda