input: from typing import List
  
  def VersionControl(lines: List[str]) -> None:
      """Implement a basic version control system in Python that keeps track of changes in the code.
      The system should allow for committing changes and restoring to a previous version.
      The commit method should write the current state of the lines to a log file with a unique mark.
      The restore method should revert the lines to the state stored at the previous mark in the log file.
      
      Example:
      lines = ["line1", "line2", "line3"]
      vc = VersionControl(lines)
      vc.commit()  # log_file.txt contains: "1: ['line1', 'line2', 'line3']"
      lines.append("line4")
      vc.commit()  # log_file.txt contains: "1: ['line1', 'line2', 'line3']\n2: ['line1', 'line2', 'line3', 'line4']"
      vc.restore()  # lines are now: ['line1', 'line2', 'line3']
      """
output:     
      import os
      import json
  
      class VersionControl:
          def __init__(self, lines: List[str]):
              self.lines = lines
              self.log_file = "log_file.txt"
              self.mark = 0
              self.load_log()
  
          def load_log(self):
              if os.path.exists(self.log_file):
                  with open(self.log_file, 'r') as f:
                      log_content = f.read()
                      if log_content:
                          self.log = json.loads(log_content)
                          self.mark = max(self.log.keys())
                      else:
                          self.log = {}
              else:
                  self.log = {}
  
          def commit(self):
              self.mark += 1
              self.log[self.mark] = self.lines[:]
              with open(self.log_file, 'w') as f:
                  f.write(json.dumps(self.log))
  
          def restore(self):
              if self.mark > 0:
                  self.mark -= 1
                  self.lines[:] = self.log[self.mark]
  