class_docstr: Abbreviation Preprocessor - parse text for abbr references. 
class_docstr_tok: ["Abbreviation","Preprocessor","-","parse","text","for","abbr","references","."]
docstr: Given a string, returns an regex pattern to match that string.
  
  'HTML' -> r'(?P<abbr>[H][T][M][L])'
  
  Note: we force each char as a literal match (in brackets) as we don't
  know what they will be beforehand.
docstr_tok: ["Given","a","string",",","returns","an","regex","pattern","to","match","that","string",".","'HTML","'","-",">","r","'","(","?","P","<","abbr",">","[","H","]","[","T","]","[","M","]","[","L","]",")","'","Note",":","we","force","each","char","as","a","literal","match","(","in","brackets",")","as","we","don't","know","what","they","will","be","beforehand","."]
code: def _generate_pattern(self, text: str) -> str:
      """
      Given a string, returns an regex pattern to match that string.
  
      'HTML' -> r'(?P<abbr>[H][T][M][L])'
  
      Note: we force each char as a literal match (in brackets) as we don't
      know what they will be beforehand.
  
      """
      chars = list(text)
      for i in range(len(chars)):
          chars[i] = r"[%s]" % chars[i]
      return r"(?P<abbr>\b%s\b)" % (r"".join(chars))
  
file_path: markdown/markdown/extensions/abbr.py
imports: from __future__ import annotations
  from .None import Extension
  from ..blockprocessors import BlockProcessor
  from ..inlinepatterns import InlineProcessor
  from ..util import AtomicString
  import re
  import xml.etree.ElementTree
label_desc: Use image node_id 3 for calling the AbbrPreprocessor obj's underlying member method code with example usage: obj._generate_pattern(text) and returns: unknown