explain this code in matlab in matlab

This code reads an image named "lena.png" into MATLAB using the imread function and then converts the image into grayscale using the rgb2gray function. Then, the code applies a 3x3 median filter to remove any noise present in the image. Finally, the filtered image is displayed using the imshow function.

main.m
% Read the image into MATLAB
I = imread('lena.png');

% Convert the image to grayscale
I = rgb2gray(I);

% Apply a median filter to remove noise
I = medfilt2(I, [3 3]);

% Display the filtered image
imshow(I);
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This code can be used as a basic image processing example to read, process, and display an image.