Getting requests.exceptions.InvalidHeader: Header part (1) from ('Sec-Gpc', 1) must be of type str or bytes, not <class 'int'> though Chrome sends it

I get requests.exceptions.InvalidHeader: Header part (1) from ('Sec-Gpc', 1) must be of type str or bytes, not <class 'int'> when trying to use the Sec-Gpc attribute in a header:

headers = {
    ...,
    "Sec-Gpc": 1,
    ...
}

I tried checking MDN, but the browser compatibility table says Chrome doesn't support it, but when I check the request headers, Chrome sends it.

In this issue, an extension is said to modify the headers and that Chrome doesn't support it, but I don't have that extension in my requests/driver. So, why do I get the error, and how do I pass the attribute, preferably without any third-party libraries?

Don't put integer as value in headers, convert it to string. E.g.:

import requests

url = "https://httpbin.org/headers"

headers = {"Sec-Gpc": "1"}

print(requests.get(url, headers=headers).text)

Prints:

{
  "headers": {
    "Accept": "*/*", 
    "Accept-Encoding": "gzip, deflate, br", 
    "Host": "httpbin.org", 
    "Sec-Gpc": "1", 
    "User-Agent": "python-requests/2.31.0", 
  }
}