code: @Override
      public String getFunction(String variable, String function, Object... args) {
          return getFunction(variable + "." + function, args);
      }
docs: Gets a function as a String, which then can be passed to the execute()
  method.
  
  @param variable The variable to invoke the function on.
  @param function The function to invoke
  @param args Arguments the function requires
  @return A string which can be passed to the JavaScript environment to
  invoke the function