Pygame smooth movement

Question

How can I get a pygame rect to move smoothly? Like if I update the x position by 2 it looks smooth but if I update it by bigger number like 25 it teleports to the position. Also, if possible, can this work for decimals also?

Visual Representation

import pygame
import math

GREEN = (20, 255, 140)
GREY = (210, 210 ,210)
WHITE = (255, 255, 255)
RED = (255, 0, 0)
PURPLE = (255, 0, 255)
BLUE = (0, 0, 255)
BLACK = (0, 0, 0)

class Dot(pygame.sprite.Sprite):
    # This class represents a car. It derives from the "Sprite" class in Pygame.
    def __init__(self, color, width, height):

        # Call the parent class (Sprite) constructor
        super().__init__()

        # Pass in the color of the car, and its x and y position, width and height.
        # Set the background color and set it to be transparent
        self.image = pygame.Surface([width, height])
        self.image.fill(WHITE)
        self.image.set_colorkey(WHITE)
        self.color = color
        self.width = width
        self.height = height
        pygame.draw.rect(self.image, self.color, [0, 0, self.width, self.height])
        self.rect = self.image.get_rect()

Answer 1

How can I get a pygame rect to move smoothly?

If your rectangle has to move 25px per frame, then the it makes no sens to draw the rectangles at the positions in between. The display is updated once per frame and it make no sens at all to draw the rectangle at the positions in between.
Possibly you have to less frames per second. In that case you have to increase the framerate and you can decrease the movement. Note, the human eye can just process a certain number of images per second. The trick is that you generate enough frames, that the movement appears smooth for the human eye.

pygame.Rect can store integral values only. If you want to operate with a very high framerate and floating accuracy, then you have to store the position of the object in separate floating point attributes. Synchronize the rounded position to the rectangle attribute. Note, you cannot draw on a "half" pixel of the window (at least in pygame).

e.g.:

class Dot(pygame.sprite.Sprite):
    # This class represents a car. It derives from the "Sprite" class in Pygame.
    def __init__(self, color, x, y, width, height):

        # Call the parent class (Sprite) constructor
        super().__init__()

        # Pass in the color of the car, and its x and y position, width and height.
        # Set the background color and set it to be transparent
        self.x = x
        self.y = y
        self.image = pygame.Surface([width, height])
        self.image.fill(self.color)
        self.rect = self.image.get_rect(center = (round(x), round(y)))

    def update(self):
        # update position of object (change `self.x`,  ``self.y``)
        # [...]

        # synchronize position to `.rect`
        self.rect.center = (round(x), round(y))