code: def parse_cg(self):
          
  
          # skip call graph header
          line = self.readline()
          while self._cg_header_re.match(line):
              line = self.readline()
  
          # process call graph entries
          entry_lines = []
          # An EOF in readline terminates the program without returning.
          while not self._cg_footer_re.match(line):
              if line.isspace():
                  self.parse_cg_entry(entry_lines)
                  entry_lines = []
              else:
                  entry_lines.append(line)            
              line = self.readline()
docs: Parse the call graph.