python - Error: Unresolved reference 'selenium' What is the reason? -

# -*- coding: utf-8 -*- selenium import selenium import unittest, time, re  class rc(unittest.testcase):     def setup(self):         self.verificationerrors = []         self.selenium = selenium("localhost", 4444, "*chrome", "http://stackoverflow.com/")         self.selenium.start()      def test_rc(self):         sel = self.selenium         sel.open("/")         sel.type("id=kw", "selenium")         sel.click("id=container")         sel.click("id=su")      def teardown(self):         self.selenium.stop()         self.assertequal([], self.verificationerrors)  if __name__ == "__main__":     unittest.main() 

this recorded selenium ide, selenium remote control code. in ide test passed.

  in pycharm open, first line (from selenium import selenium)

there error: unresolved reference 'selenium'

what reason?

my environment is

• python3.5
• selenium3.3.1
• selenium-server-standalone-3.3.1.jar