{4,20}matches between 4 and 20 characters from the set below:
0-9one character from 0 (4810) to 9 (5710)
(the literal ( (4010 / 508 / 2816)
)the literal ) (4110 / 518 / 2916)
\-the literal - (4510 / 558 / 2D16)
\sany whitespace character
+the literal + (4310 / 538 / 2B16)