How to use the arcade.key.LEFT function in arcade

def on_key_press(self, key, modifiers):
        """Called whenever a key is pressed. """

        if key == arcade.key.UP:
            self.player_sprite.change_y = MOVEMENT_SPEED
        elif key == arcade.key.DOWN:
            self.player_sprite.change_y = -MOVEMENT_SPEED
        elif key == arcade.key.LEFT:
            self.player_sprite.change_x = -MOVEMENT_SPEED
        elif key == arcade.key.RIGHT:
            self.player_sprite.change_x = MOVEMENT_SPEED

def on_key_press(self, key, modifiers):
        """Called whenever a key is pressed. """

        if key == arcade.key.UP:
            self.player_sprite.change_y = MOVEMENT_SPEED
        elif key == arcade.key.DOWN:
            self.player_sprite.change_y = -MOVEMENT_SPEED
        elif key == arcade.key.LEFT:
            self.player_sprite.change_x = -MOVEMENT_SPEED
        elif key == arcade.key.RIGHT:
            self.player_sprite.change_x = MOVEMENT_SPEED

def on_key_release(self, key, modifiers):
        """Called when the user releases a key. """

        if key == arcade.key.UP or key == arcade.key.DOWN:
            self.player_sprite.change_y = 0
        elif key == arcade.key.LEFT or key == arcade.key.RIGHT:
            self.player_sprite.change_x = 0

def on_key_press(self, key, modifiers):
        """
        Called whenever the mouse moves.
        """
        if key == arcade.key.UP:
            if self.physics_engine.can_jump():
                self.player_sprite.change_y = JUMP_SPEED
        elif key == arcade.key.LEFT:
            self.player_sprite.change_x = -MOVEMENT_SPEED
        elif key == arcade.key.RIGHT:
            self.player_sprite.change_x = MOVEMENT_SPEED

def on_key_press(self, key, modifiers):
        """Called whenever a key is pressed. """

        if key == arcade.key.UP:
            self.player_sprite.change_y = MOVEMENT_SPEED
        elif key == arcade.key.DOWN:
            self.player_sprite.change_y = -MOVEMENT_SPEED
        elif key == arcade.key.LEFT:
            self.player_sprite.change_x = -MOVEMENT_SPEED
        elif key == arcade.key.RIGHT:
            self.player_sprite.change_x = MOVEMENT_SPEED

def on_key_press(self, key, modifiers):
        """
        Handle user key presses
        User goes left, move -1
        User goes right, move 1
        Rotate stone,
        or drop down
        """
        if key == arcade.key.LEFT:
            self.move(-1)
        elif key == arcade.key.RIGHT:
            self.move(1)
        elif key == arcade.key.UP:
            self.rotate_stone()
        elif key == arcade.key.DOWN:
            self.drop()

def on_key_release(self, key, modifiers):
        """Called when the user releases a key. """

        if key == arcade.key.UP or key == arcade.key.DOWN:
            self.player_sprite.change_y = 0
        elif key == arcade.key.LEFT or key == arcade.key.RIGHT:
            self.player_sprite.change_x = 0

def on_key_press(self, key, modifiers):
        """
        Called whenever a key is pressed down.
        """
        if key == arcade.key.UP:
            if self.physics_engine.can_jump():
                self.player_sprite.change_y = JUMP_SPEED
        elif key == arcade.key.LEFT:
            self.player_sprite.change_x = -MOVEMENT_SPEED
        elif key == arcade.key.RIGHT:
            self.player_sprite.change_x = MOVEMENT_SPEED

def on_key_press(self, key, modifiers):
        """ Called whenever a key is pressed. """

        if key == arcade.key.UP:
            self.player_sprite.change_y = MOVEMENT_SPEED
        elif key == arcade.key.DOWN:
            self.player_sprite.change_y = -MOVEMENT_SPEED
        elif key == arcade.key.LEFT:
            self.player_sprite.change_x = -MOVEMENT_SPEED
        elif key == arcade.key.RIGHT:
            self.player_sprite.change_x = MOVEMENT_SPEED

def on_key_press(self, key, modifiers):
        """
        Called whenever the mouse moves.
        """
        if key == arcade.key.UP:
            self.player.force[1] = MOVEMENT_SPEED
        elif key == arcade.key.DOWN:
            self.player.force[1] = -MOVEMENT_SPEED
        elif key == arcade.key.LEFT:
            self.player.force[0] = -MOVEMENT_SPEED
        elif key == arcade.key.RIGHT:
            self.player.force[0] = MOVEMENT_SPEED