code: def get_oldest_commit_date(self):
          '''
          Get datetime of oldest commit involving this file
  
          :returns: Datetime of oldest commit
          '''
          oldest_commit = self.get_oldest_commit()
          return self.git.get_commit_date(oldest_commit, self.tz_namef get_oldest_commit_date(self):
          '''
          Get datetime of oldest commit involving this file
  
          :returns: Datetime of oldest commit
          '''
          oldest_commit = self.get_oldest_commit()
          return self.git.get_commit_date(oldest_commit, self.tz_name)
docs: Get datetime of oldest commit involving this file
  
          :returns: Datetime of oldest commit