Without leveraging the Python API but using the REST API instead, I managed to achieve my goal using this:
import requests
import json
import config
def main():
session = requests.Session()
sess = session.post(f"https://{config.server}/rest/com/vmware/cis/session", auth=(config.username, config.password), verify=False)
session_id = sess.json()['value']
get_upgrade_url = f"https://{config.server}/api/vcenter/deployment/upgrade"
response = session.get(get_upgrade_url, headers={'vmware-api-session-id': session_id}, verify=False)
########### JSON Handling
json_object = json.loads(response.text)
json_formatted_str = json.dumps(json_object, indent=2)
print(json_formatted_str)
######################
check_upgrade_url = f"https://{config.server}/rest/appliance/update/pending?source_type=LAST_CHECK"
check_response = session.get(check_upgrade_url, headers={'vmware-api-session-id': session_id}, verify=False)
print(check_response)
########### JSON Handling
json_object = json.loads(check_response.text)
json_formatted_str = json.dumps(json_object, indent=2)
print(json_formatted_str)
######################
if __name__ == "__main__":
main()