password generator with 5 letters, 3 numbers and one special character in php

main.php
function generatePassword() {
    // Set of characters to be used in password
    $chars = "abcdefghijklmnopqrstuvwxyz";
    $nums = "0123456789";
    $specialChars = "!@#$%^&*()_-=+{}[]";

    // Generate random strings of required length
    $letters = substr(str_shuffle($chars), 0, 5);
    $numbers = substr(str_shuffle($nums), 0, 3);
    $specialChar = substr(str_shuffle($specialChars), 0, 1);

    // Combine all the generated strings
    $password = $letters . $numbers . $specialChar;

    // Shuffle the final password
    $password = str_shuffle($password);

    return $password;
}

echo "Generated Password: " . generatePassword();
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