如何在Pylucene 8.6.1中创建自定义分析器？

import lucene
from org.apache.lucene.analysis.standard import StandardAnalyzer
from org.apache.lucene.analysis.util import CharTokenizer
from org.apache.lucene.analysis.tokenattributes import CharTermAttribute
from java.io import StringReader

class CustomAnalyzer(CharTokenizer):
    def isTokenChar(self, c):
        # 自定义规则判断字符是否可作为标记
        # 返回True表示是，返回False表示不是
        return c.isalnum()
        
    def normalize(self, c):
        # 自定义规则对字符进行标准化处理
        # 返回标准化后的字符
        return c.lower()

analyzer = CustomAnalyzer()

text = "This is a sample text."
tokenizer = analyzer.tokenStream("text", StringReader(text))
tokenizer.reset()

termAttr = tokenizer.addAttribute(CharTermAttribute.class_)
while tokenizer.incrementToken():
    print(termAttr.toString())