code: def whitespace_around_comma(logical_line):
      r
      line = logical_line
      for m in WHITESPACE_AFTER_COMMA_REGEX.finditer(line):
          found = m.start() + 1
          if '\t' in m.group():
              yield found, "E242 tab after '%s'" % m.group()[0]
          else:
              yield found, "E241 multiple spaces after '%s'" % m.group()[0]
docs: r"""Avoid extraneous whitespace after a comma or a colon.
  
      Note: these checks are disabled by default
  
      Okay: a = (1, 2)
      E241: a = (1,  2)
      E242: a = (1,\t2)