input: Write a function to create a TicTacToe game in Python with methods to initialize the game, display the board, and check for a win condition. The function should include an assert statement to verify the correctness of the check_win method.
  assert TicTacToe().check_win() == False
output: class TicTacToe:
      def __init__(self):
          self.board = [[' ' for _ in range(3)] for _ in range(3)]
  
      def display_board(self):
          for row in self.board:
              print('|'.join(row))
              print('-' * 5)
  
      def check_win(self):
          for row in self.board:
              if row[0] == row[1] == row[2] != ' ':
                  return True
          for col in range(3):
              if self.board[0][col] == self.board[1][col] == self.board[2][col] != ' ':
                  return True
          if self.board[0][0] == self.board[1][1] == self.board[2][2] != ' ':
              return True
          if self.board[0][2] == self.board[1][1] == self.board[2][0] != ' ':
              return True
          return False