My Pygame surface is not getting pushed back down by gravity

Question

I would really like the purple_idle_rect to be able to jump in the air, then get pulled down by gravity. What really happens here is that once I jump, I am stuck in the air then once I press the jump button again I fall. Basically, I need to press the up arrow key twice to fully jump and land on the ground.

import pygame

# import n stuff
import pygame
pygame.init()

# Screen and setup
Screen = pygame.display.set_mode((900, 500))

# Velocity
Velocity = 8

# Purple who sleep
purple_sleeping = pygame.transform.scale(pygame.image.load("purple_guy_sleeping.png"), (100, 100))
purple_sleeping_rect = purple_sleeping.get_rect(center=(450, 302))

# Purple who stand
purple_idle = pygame.transform.scale(pygame.image.load("purple_man_idle.png"), (100, 100))
purple_idle_rect = purple_idle.get_rect(midbottom = (100,360))

# The ground
ground = pygame.transform.scale(pygame.image.load("a2889b85d5c7122.png"), (800, 100))
# Main loop
Run = True
FPS = 60
Clock = pygame.time.Clock()
#  All of our keys
pressed_keys = {"left": False, "right": False}

#  Gravity
player_gravity = 0
isJump = False
while Run:
    pygame.display.update()
    Screen.fill("black")
    Screen.blit(ground, (45, 350))
    Screen.blit(purple_sleeping, purple_sleeping_rect)
    Screen.blit(purple_idle, purple_idle_rect)
    Clock.tick(FPS)
    keys = pygame.key.get_pressed()
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            pygame.quit()
            exit()
        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_LEFT:
                pressed_keys["left"] = True
            if event.key == pygame.K_RIGHT:
                pressed_keys["right"] = True
            if event.key == pygame.K_UP and purple_idle_rect.bottom == 360:
                player_gravity -=20
        elif event.type == pygame.KEYUP:
            if event.key == pygame.K_LEFT:
                pressed_keys["left"] = False
            if event.key == pygame.K_RIGHT:
                pressed_keys["right"] = False
            if purple_idle_rect.bottom == 360:
                isJump = False
                if not isJump:
                    purple_idle_rect.bottom = 360
            if purple_idle_rect.bottom < 360:
                isJump = True
                if isJump:
                    player_gravity += 20

    if pressed_keys["left"]:  # == True is implied here
        purple_idle_rect.x -= 10
    if pressed_keys["right"]:
        purple_idle_rect.x += 10
    purple_idle_rect.bottom += player_gravity
    if purple_idle_rect.bottom > 360:
        purple_idle_rect.bottom = 360
    pygame.display.update()

Answer 1

I changed your jump a bit, this is how it works for me:

player_gravity = 20
isJump = False
while Run:
    # pygame.display.update()
    Screen.fill("black")
    Screen.blit(ground, (45, 350))
    Screen.blit(purple_sleeping, purple_sleeping_rect)
    Screen.blit(purple_idle, purple_idle_rect)

    keys = pygame.key.get_pressed()
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            pygame.quit()
            exit()
        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_LEFT:
                pressed_keys["left"] = True
            if event.key == pygame.K_RIGHT:
                pressed_keys["right"] = True
            if event.key == pygame.K_UP and purple_idle_rect.bottom == 360:
                isJump = True
                player_gravity = -player_gravity
            
        elif event.type == pygame.KEYUP:
            if event.key == pygame.K_LEFT:
                pressed_keys["left"] = False
            if event.key == pygame.K_RIGHT:
                pressed_keys["right"] = False

    if pressed_keys["left"]:  # == True is implied here
        purple_idle_rect.x -= 10
    if pressed_keys["right"]:
        purple_idle_rect.x += 10
    
    # Set gravity back
    if isJump:
        player_gravity += 1
        if player_gravity >= 20:
            isJump = False

    purple_idle_rect.bottom += player_gravity
    if purple_idle_rect.bottom > 360:
        purple_idle_rect.bottom = 360

    pygame.display.update()
    Clock.tick(FPS)

Perhaps you understand everything well, if you do not ask in the comments. I hope I helped you, Adam