class_docstr: :class:`.History` class that stores all strings in a file.
class_docstr_tok: [":","class",":","`",".History","`","class","that","stores","all","strings","in","a","file","."]
code: def _load(self):
      lines = []
  
      def add():
          if lines:
              # Join and drop trailing newline.
              string = "".join(lines)[:-1]
  
              self.strings.append(string)
  
      if os.path.exists(self.filename):
          with open(self.filename, "rb") as f:
              for line in f:
                  line = line.decode("utf-8")
  
                  if line.startswith("+"):
                      lines.append(line[1:])
                  else:
                      add()
                      lines = []
  
              add()
  
imports: from __future__ import unicode_literals
  from abc import ABCMeta, abstractmethod
  from six import with_metaclass
  import datetime
  import os
label_desc: Use image node_id 2 for calling the FileHistory obj's underlying member method code with example usage: obj._load() without return types