code: def number(self):
      localctx = LaTeXParser.NumberContext(self, self._ctx, self.state)
      self.enterRule(localctx, 42, self.RULE_number)
      try:
          self.enterOuterAlt(localctx, 1)
          self.state = 274
          self._errHandler.sync(self)
          _alt = 1
          while _alt != 2 and _alt != ATN.INVALID_ALT_NUMBER:
              if _alt == 1:
                  self.state = 273
                  self.match(LaTeXParser.DIGIT)
  
              else:
                  raise NoViableAltException(self)
              self.state = 276
              self._errHandler.sync(self)
              _alt = self._interp.adaptivePredict(
                  self._input, 23, self._ctx
              )
  
          self.state = 284
          self._errHandler.sync(self)
          _alt = self._interp.adaptivePredict(
              self._input, 24, self._ctx
          )
          while _alt != 2 and _alt != ATN.INVALID_ALT_NUMBER:
              if _alt == 1:
                  self.state = 278
                  self.match(LaTeXParser.T__0)
                  self.state = 279
                  self.match(LaTeXParser.DIGIT)
                  self.state = 280
                  self.match(LaTeXParser.DIGIT)
                  self.state = 281
                  self.match(LaTeXParser.DIGIT)
              self.state = 286
              self._errHandler.sync(self)
              _alt = self._interp.adaptivePredict(
                  self._input, 24, self._ctx
              )
  
          self.state = 293
          self._errHandler.sync(self)
          la_ = self._interp.adaptivePredict(self._input, 26, self._ctx)
          if la_ == 1:
              self.state = 287
              self.match(LaTeXParser.T__1)
              self.state = 289
              self._errHandler.sync(self)
              _alt = 1
              while _alt != 2 and _alt != ATN.INVALID_ALT_NUMBER:
                  if _alt == 1:
                      self.state = 288
                      self.match(LaTeXParser.DIGIT)
  
                  else:
                      raise NoViableAltException(self)
                  self.state = 291
                  self._errHandler.sync(self)
                  _alt = self._interp.adaptivePredict(
                      self._input, 25, self._ctx
                  )
  
      except RecognitionException as re:
          localctx.exception = re
          self._errHandler.reportError(self, re)
          self._errHandler.recover(self, re)
      finally:
          self.exitRule()
      return localctx
  
imports: from antlr4 import *
  from io import StringIO
  import sys
label_desc: Use image node_id 23 for calling the LaTeXParser obj's underlying member method code with example usage: obj.number() and returns: localctx