[Python] pico W server response header problems

I tried to set up a small server on which I could live detect the value of all the GPIO pins on the pico pi W first I found this example which worked perfectly then i added the function to add the states of the GPIO pins to the html after some stuff I made it work but I did not save it. And now I can not figure out how to get it to work. Line where I get: OSError -1
​

conn.send(f'HTTP/1.0 200 OK\r\nContent-type: text/html\r\n\r\n')

I also tried a different headers for example:

conn.send(f'HTTP/1.0 200 OK\r\nContent-type: text/html\r\nContent-Length: {len(response)}\r\n\r\n')

But None of them seemed to work

Whole code for reference:


# Import necessary modules
import network
import socket
import time
import random
from machine import Pin

# Create an LED object on pin 'LED'
led = Pin('LED')

# Wi-Fi credentials
ssid = 'SSID'
password = 'PASWORD'
def get_gpio_states():
gpio_html = ""
for pin_number in range(0, 28): # Adjust based on your setup
pin = Pin(pin_number, Pin.IN) # Set GPIO as input
state = pin.value() # Read GPIO state
gpio_html += f"<tr><td>{pin_number}</td><td>{state}</td></tr>"
return gpio_html
# HTML template for the webpage

def webpage(random_value, state,gpio_states):
gpio_states =gpio_states
html = f"""
<html>
<head>
<title>Pico Web Server</title>
<meta name="viewport" content="width=device-width, initial-scale=1">
</head>
<body>
<h1>Raspberry Pi Pico Web Server</h1>
<h2>Led Control</h2>
<form action="./lighton">
<input type="submit" value="Light on">
</form><br>
<form action="./lightoff">
<input type="submit" value="Light off">
</form>
<p>LED state: {state}</p>
<h2>Fetch New Value</h2>
<form action="./value">
<input type="submit" value="Fetch value">
</form>
<p>Fetched value: {random_value}</p>
<h1>GPIO States</h1>
<table border="1">
<tr>
<th>GPIO Pin</th>
<th>State</th>
</tr>
{gpio_states}
</table>
</body>
</html>
"""
return str(html)

# Connect to WLAN
wlan = network.WLAN(network.STA_IF)
wlan.active(True)
wlan.connect(ssid, password)

# Wait for Wi-Fi connection
connection_timeout = 20
while connection_timeout > 0:
if wlan.status() >= 3:
break
connection_timeout -= 1
print('Waiting for Wi-Fi connection...')
time.sleep(1)

# Check if connection is successful
if wlan.status() != 3:
raise RuntimeError('Failed to establish a network connection')
else:
print('Connection successful!')
network_info = wlan.ifconfig()
print('IP address:', network_info[0])

# Set up socket and start listening
addr = socket.getaddrinfo('0.0.0.0', 80)[0][-1]
s = socket.socket()
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
s.bind(addr)
s.listen()

#print('Listening on', addr)

# Initialize variables
state = "OFF"
random_value = 0

# Main loop to listen for connections
while True:
try:
conn, addr = s.accept()
print('Got a connection from', addr, conn)

# Receive and parse the request
request = conn.recv(1024)
request = str(request)
print('Request content,',repr(request))
if len(request) == 0:
print('Received empty request')
continue # Skip to the next iteration of the loop

try:
request = request.split()[1]
print('Request:', request)
except IndexError as e:
print(e)
continue

# Process the request and update variables
if request == '/lighton?':
print("LED on")
led.on()
state = "ON"
#response = "ON"
elif request == '/lightoff?':
led.off()
state = 'OFF'
elif request == '/value?':
random_value = random.randint(0, 20)
elif request == '/': # Handle the root request
#response = "Welcome to the pico web server"
random_value = 0 # Set default random value if needed
elif request == '/favicon.ico':
print("Favicon requested, ignoring.")
continue # Skip further processing for favicon

# Generate HTML response
gpio_states = get_gpio_states()
response = webpage(random_value, state, gpio_states)
# Send the HTTP response and close the connection
conn.send(f'HTTP/1.0 200 OK\r\nContent-type: text/html\r\n\r\n')
conn.send(response)

finally:
print('conn closed')
conn.close()

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