code: def token_at_cursor(code, pos=0):
      
      l = len(code)
      end = start = pos
      # Go forwards while we get alphanumeric chars
      while end < l and code[end].isalpha():
          end += 1
      # Go backwards while we get alphanumeric chars
      while start > 0 and code[start-1].isalpha():
          start -= 1
      # If previous character is a %, add it (potential magic)
      if start > 0 and code[start-1] == '%':
          start -= 1
      return code[start:end], start
docs: Find the token present at the passed position in the code buffer
       :return (tuple): a pair (token, start_position)