class_docstr: Process blockquotes. 
class_docstr_tok: ["Process","blockquotes","."]
docstr: Remove `>` from beginning of a line. 
docstr_tok: ["Remove","`",">","`","from","beginning","of","a","line","."]
code: def clean(self, line: str) -> str:
      """Remove `>` from beginning of a line."""
      m = self.RE.match(line)
      if line.strip() == ">":
          return ""
      elif m:
          return m.group(2)
      else:
          return line
  
imports: from __future__ import annotations
  import logging
  import re
  import xml.etree.ElementTree
  from typing import TYPE_CHECKING, Any
  from .None import util
  from .blockparser import BlockParser
label_desc: Use image node_id 3 for calling the BlockQuoteProcessor obj's underlying member method code with example usage: obj.clean(line) and returns: str, m, line