def _compose(f, g):
 def _exec(x):
  ret = g(x)
  if (ret is not None):
   ret = HtmlPageRegion(ret.htmlpage, remove_tags(ret.text_content))
   return f(ret)
  return None
 return _exec

def _compose ( f , g ) : def _exec ( x ) : ret = g ( x ) if ( ret is not None ) : ret = HtmlPageRegion ( ret . htmlpage , remove_tags ( ret . text_content ) ) return f ( ret ) return None return _exec
given unary functions f and g .