code: def scan_until(self, regex):
          
          return self.search_full(regex, return_string=True, advance_pointer=True)
docs: Search for a pattern from the current position.
  
          If a match is found, advances the scan pointer and returns the matched
          string, from the current position *up to* the end of the match.
          Otherwise returns ``None``.
  
              >>> s = Scanner("test string")
              >>> s.pos
              0
              >>> s.scan_until(r'foo')
              >>> s.scan_until(r'bar')
              >>> s.pos
              0
              >>> s.scan_until(r' ')
              'test '
              >>> s.pos
              5