code: def argument_mutation(children, context, **_):
      
      if len(context.stack) >= 3 and context.stack[-3].type in ('power', 'atom_expr'):
          stack_pos_of_power_node = -3
      elif len(context.stack) >= 4 and context.stack[-4].type in ('power', 'atom_expr'):
          stack_pos_of_power_node = -4
      else:
          return
  
      power_node = context.stack[stack_pos_of_power_node]
  
      if power_node.children[0].type == 'name' and power_node.children[0].value in context.dict_synonyms:
          c = children[0]
          if c.type == 'name':
              children = children[:]
              children[0] = Name(c.value + 'XX', start_pos=c.start_pos, prefix=c.prefix)
              return children
docs: :type context: Context