docs: def get_warcinfo(self):
  		''' 
  		Returns WARCINFO record from the archieve as a single string including
  		WARC header. Expects the record to be in the beginning of the archieve,
  		otherwise it will be not found.
  		'''
  		if self.searched_for_warcinfo:
  			return self.warcinfo
  		prev_line = None
  		in_warcinfo_record = False
  		self.searched_for_warcinfo = True
  		for line in self.file_object:
  			if not in_warcinfo_record:
  				if line[:11] == b'WARC-Type: ':
  					if line[:19] == b'WARC-Type: warcinfo':
  						in_warcinfo_record = True
  						warcinfo_lines = [prev_line, line]
  					else:
  						self.warcinfo = None
  						break
  			else:
  				if line[0:1] == self.w_letter and self.warc_header_re.match(line):
  					self.warcinfo = b''.join(warcinfo_lines)
  					break
  				warcinfo_lines.append(line)
  			prev_line = line
  		self.file_object.seek(0)
  		return self.warcinfo