Brake master cylinder fluid filter removal...

[Exvec]

A simple but irritating problem.I need to remove the little filter from the master cylinder reservoir to enable me suck up some of the old Brake fluid and replace with new fluid,as i'm renewing the fluid after maybe  4 years of being in the system.Partial removal of the old oil helps make the job quicker and also uses less new fluid.So ?how do we get the little blighter out.Cheers.