When using RequestsCookieJar to set a cookie with an empty string ('') or 0 as the value, it cannot be retrieved properly afterward.

[mengxunQAQ]

When using RequestsCookieJar to set a cookie with an empty string ('') or 0 as the value, it cannot be retrieved properly afterward.

Expected Result

It can be retrieved properly after being set.

Actual Result

It cannot be retrieved properly after being set.

Reproduction Steps

from requests.cookies import RequestsCookieJar

jar = RequestsCookieJar()

jar.set('token', 0, domain='example.com', path='/')

print("Jar contents:", list(jar.items()))  # [('token', 0)]
print("jar.get:", jar.get('token', domain='example.com', path='/'))  # it should return 0 instead of None.

try:
    print("jar['token']:", jar['token'])  # it should return 0 instead of raising an error.
except KeyError as e:
    print("KeyError raised unexpectedly:", e)

System Information

$ python -m requests.help

{
  "chardet": {
    "version": null
  },
  "charset_normalizer": {
    "version": "2.0.12"
  },
  "cryptography": {
    "version": ""
  },
  "idna": {
    "version": "3.7"
  },
  "implementation": {
    "name": "CPython",
    "version": "3.6.8"
  },
  "platform": {
    "release": "3.10.0-1160.119.1.el7.x86_64",
    "system": "Linux"
  },
  "pyOpenSSL": {
    "openssl_version": "",
    "version": null
  },
  "requests": {
    "version": "2.27.1"
  },
  "system_ssl": {
    "version": "100020bf"
  },
  "urllib3": {
    "version": "1.26.19"
  },
  "using_charset_normalizer": true,
  "using_pyopenssl": false
}