parameters: (url, https=False)
return_statement: return url
docstring: author: windows2000
      function:
          add 'http://' or 'https://' prefix to a url if missed
docstring_summary: author: windows2000
      function:
          add 'http://' or 'https://' prefix to a url if missed
docstring_tokens: author : windows2000 function : add http : // or https : // prefix to a url if missed
function: def normalize_url(url, https=False):
      '''
      author: windows2000
      function:
          add 'http://' or 'https://' prefix to a url if missed
      '''
      if not url:
          return
      elif url.startswith(('http://', 'https://')):
          return url
      if not https:
          url = 'http://' + url
      else:
          url = 'https://' + url
      return url
function_tokens: def normalize_url ( url , https = False ) : if not url : return elif url . startswith ( ( 'http://' , 'https://' ) ) : return url if not https : url = 'http://' + url else : url = 'https://' + url return url