code: def _attempt_proof_all(
      self, current, context, agenda, accessible_vars, atoms, debug
  ):
      try:
          current._used_vars
      except AttributeError:
          current._used_vars = set()
  
      # if there are accessible_vars on the path
      if accessible_vars:
          # get the set of bound variables that have not be used by this AllExpression
          bv_available = accessible_vars - current._used_vars
  
          if bv_available:
              variable_to_use = list(bv_available)[0]
              debug.line("--> Using '%s'" % variable_to_use, 2)
              current._used_vars |= {variable_to_use}
              agenda.put(
                  current.term.replace(
                      current.variable, variable_to_use
                  ),
                  context,
              )
              agenda[Categories.ALL].add((current, context))
              return self._attempt_proof(
                  agenda, accessible_vars, atoms, debug + 1
              )
  
          else:
              # no more available variables to substitute
              debug.line("--> Variables Exhausted", 2)
              current._exhausted = True
              agenda[Categories.ALL].add((current, context))
              return self._attempt_proof(
                  agenda, accessible_vars, atoms, debug + 1
              )
  
      else:
          new_unique_variable = VariableExpression(unique_variable())
          debug.line("--> Using '%s'" % new_unique_variable, 2)
          current._used_vars |= {new_unique_variable}
          agenda.put(
              current.term.replace(
                  current.variable, new_unique_variable
              ),
              context,
          )
          agenda[Categories.ALL].add((current, context))
          agenda.mark_alls_fresh()
          return self._attempt_proof(
              agenda,
              accessible_vars | {new_unique_variable},
              atoms,
              debug + 1,
          )
  
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 23 for calling the TableauProver obj's underlying member method code with example usage: obj._attempt_proof_all(current, context, agenda, accessible_vars, atoms, debug) and returns: self, self, self