class_docstr: Manage the invocation of a WSGI application
class_docstr_tok: ["Manage","the","invocation","of","a","WSGI","application"]
docstr: Make any necessary header changes or defaults
  
  Subclasses can extend this to add other defaults.
docstr_tok: ["Make","any","necessary","header","changes","or","defaults","Subclasses","can","extend","this","to","add","other","defaults","."]
code: def cleanup_headers(self):
      """Make any necessary header changes or defaults
  
      Subclasses can extend this to add other defaults.
      """
      if "Content-Length" not in self.headers:
          self.set_content_length()
  
imports: from .util import FileWrapper, guess_scheme, is_hop_by_hop
  from .headers import Headers
  import sys, os, time
label_desc: Use image node_id 6 for calling the BaseHandler obj's underlying member method code with example usage: obj.cleanup_headers() without return types