code: def online_help(param=None, alt_link=False):
      """
      Open online document in web browser.
  
      :param param: input parameter
      :type param: int or str
      :param alt_link: alternative link for document flag
      :type alt_link: bool
      :return: None
      """
      try:
          document_link = DOCUMENT_ADR
          if alt_link:
              document_link = DOCUMENT_ADR_ALT
          params_link_keys = sort_char_num(PARAMS_LINK.keys())
          if param in params_link_keys:
              webbrowser.open_new_tab(
                  document_link + PARAMS_LINK[param]
              )
          elif param in range(1, len(params_link_keys) + 1):
              webbrowser.open_new_tab(
                  document_link
                  + PARAMS_LINK[params_link_keys[param - 1]]
              )
          else:
              print("Please choose one parameter : \n")
              print('Example : online_help("J") or online_help(2)\n')
              for index, item in enumerate(params_link_keys):
                  print(str(index + 1) + "-" + item)
      except Exception:  # pragma: no cover
          print("Error in online help")
  
imports: from __future__ import division
  from functools import partial
  from .pycm_param import *
  from .pycm_util import rounder, sort_char_num
  import webbrowser
label_desc: Use image node_id 16 for calling a global function with example usage: online_help(param, alt_link) without return types