python/pygame test specific key to be up

So i'm trying to make a topdown game and i'm having problems with player movement. When i press key [W,A,S or D] player moves that way. But i want it to keep moving as long as button is being held down. So i change [playerMoveLeft, playerMoveRight, playerMoveDown or playerMoveUp] to 1

            if allowMovement == 1:
            if event.key == pygame.K_a:
                playerMoveLeft = 1
                print("Hello")

            if event.key == pygame.K_d:
                playerMoveRight = 1

            if event.key == pygame.K_s:
                playerMoveDown = 1

            if event.key == pygame.K_w:
                playerMoveUp = 1

            if event.key == pygame.K_LSHIFT:
                playerMoveSprint = 1
                playerSpeed = 2

So as long as one of playerMoves are 1 player should keep moving. Know the problem: When i release the key it sets all playerMoves to 0 what causes the player to stop so i'm trying to find a way to only testfor 1 specific key to be lifted up and that would set thath specific playerMove to 0.

        if event.type == pygame.KEYUP:
        playerMoveLeft = 0
        playerMoveRight = 0
        playerMoveUp = 0
        playerMoveDown = 0
        playerMoveSprint = 0

Below this text there is the Full code area for player movement

    for event in pygame.event.get():
    if event.type == pygame.QUIT:
        valmis = True

    if event.type == pygame.KEYDOWN:



############################## CONTROL PLAYER ############################
        if allowMovement == 1:
            if event.key == pygame.K_a:
                playerMoveLeft = 1
                print("Hello")

            if event.key == pygame.K_d:
                playerMoveRight = 1

            if event.key == pygame.K_s:
                playerMoveDown = 1

            if event.key == pygame.K_w:
                playerMoveUp = 1

            if event.key == pygame.K_LSHIFT:
                playerMoveSprint = 1
                playerSpeed = 2

    if event.type == pygame.KEYUP:
        playerMoveLeft = 0
        playerMoveRight = 0
        playerMoveUp = 0
        playerMoveDown = 0
        playerMoveSprint = 0

if playerMoveSprint == 1:
    playerSpeed = 1

if playerMoveLeft == 1:
    player_x -=(playerSpeed)
if playerMoveRight == 1:
    player_x +=(playerSpeed)
if playerMoveUp == 1:
    player_y -=(playerSpeed)
if playerMoveDown == 1:
    player_y +=(playerSpeed)

thanks for every one who helps!