<prompt> Fanya kazi ya Python inayoitwa is_valid_regex ambayo inachukua kitanzi kama pembejeo na inachunguza ikiwa ni usemi wa kawaida halali. kazi inapaswa kurudisha thamani ya boolean, ambapo kweli inaonyesha kwamba kitanzi cha pembejeo ni usemi wa kawaida halali na uwongo inaonyesha kwamba haifai. kazi inapaswa kutumia moduli ya re katika Python kutimiza kazi hii. syntax ya usemi wa kawaida inapaswa kufuata sheria na syntax ya usemi wa kawaida wa Python.  <response>: Re: Example Example Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: 