Programming FAQ: fix a punctuaction typo

Author: johnslavik

Doc/faq/programming.rst

@@ -1232,7 +1232,7 @@ How do you remove multiple items from a list
 As with removing duplicates, explicitly iterating in reverse with a
 delete condition is one possibility.  However, it is easier and faster
 to use slice replacement with an implicit or explicit forward iteration.
-Here are three variations.::
+Here are three variations::
 
    mylist[:] = filter(keep_function, mylist)
    mylist[:] = (x for x in mylist if keep_condition)