Break function not working on Python cisco factory reset script

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Python

Cisco

import serial
import time

# Serial port configuration
ser = serial.Serial("/dev/ttyUSB0", timeout=1)
print(f"Connecting to {ser.name}...")

# Strings for prompt detection
initPrompt = "Initializing Flash"
swPrompt = "switch:"
ynPrompt = " (y/n)?"

# Function to wait for specific prompt and send command
def wait_for_prompt_and_send(prompt, command):
    while True:
        response = ser.read_until(prompt.encode("utf-8")).decode("utf-8")
        if prompt in response:
            print(f"Found prompt: {prompt}")
            ser.write(command)
            ser.write(b"\n")
            break

# Connect and send initial break commands
ser.write(b"\r")
print("Sent carriage return...")
time.sleep(0.5)
wait_for_prompt_and_send(initPrompt, b"\x03")  # break command

# Initialize flash
wait_for_prompt_and_send(swPrompt, b"flash_init\n\n")

# Delete vlan.dat
wait_for_prompt_and_send(swPrompt, b"del flash:vlan.dat\n")
wait_for_prompt_and_send(ynPrompt, b"y\n")

# Delete config.text
wait_for_prompt_and_send(swPrompt, b"del flash:config.text\n")
wait_for_prompt_and_send(ynPrompt, b"y\n")

ser.close()

What I have tried:

I have to reset a lot of old Cisco switches so I wanted to automate the process.

Instead of holding down the physical button on the switch, the script should issue a break command after the program ran the initPrompt initializing flash. However, it doesn't do that. All I see on the Python console is that it sent the carriage return and found the prompt: initializing flash. When I open the SecureCRT session and check the status of the startup, the switch goes through the normal boot so the break definitely didn't work.

Win 10 & Python 3.10