code: def _attempt_proof_app(
      self, current, context, agenda, accessible_vars, atoms, debug
  ):
      f, args = current.uncurry()
      for i, arg in enumerate(args):
          if not TableauProver.is_atom(arg):
              ctx = f
              nv = Variable("X%s" % _counter.get())
              for j, a in enumerate(args):
                  ctx = (
                      ctx(VariableExpression(nv)) if i == j else ctx(a)
                  )
              if context:
                  ctx = context(ctx).simplify()
              ctx = LambdaExpression(nv, ctx)
              agenda.put(arg, ctx)
              return self._attempt_proof(
                  agenda, accessible_vars, atoms, debug + 1
              )
      raise Exception(
          "If this method is called, there must be a non-atomic argument"
      )
  
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 7 for calling the TableauProver obj's underlying member method code with example usage: obj._attempt_proof_app(current, context, agenda, accessible_vars, atoms, debug) and returns: self