code: def is_var_or_func_exist(content):
      
      if not isinstance(content, basestring):
          return False
  
      try:
          match_start_position = content.index("$", 0)
      except ValueError:
          return False
  
      while match_start_position < len(content):
          dollar_match = dolloar_regex_compile.match(content, match_start_position)
          if dollar_match:
              match_start_position = dollar_match.end()
              continue
  
          func_match = function_regex_compile.match(content, match_start_position)
          if func_match:
              return True
  
          var_match = variable_regex_compile.match(content, match_start_position)
          if var_match:
              return True
  
          return False
docs: check if variable or function exist