How to display OperationProxy body

[Shodiev-Shokhrukh]

from requests import Session
from zeep import Client, Settings
from zeep.plugins import HistoryPlugin
from zeep.transports import Transport

session = Session()
session.verify = True

transport = Transport(session=session)
history = HistoryPlugin()

wsdl_url = 'https://argusgate2.fitorf.ru/debug/ws/uz3?wsdl'
settings = Settings(strict=False, xml_huge_tree=True)

client = Client(
    wsdl_url,
    transport=transport,
    settings=settings, plugins=[history])
logging.getLogger("zeep").propagate = False

parametrs = {
    "a": "something",

}
def send_request(cl, **parametrs):
    r = cl.service.Request91.input(**parametrs)
    return r

a = send_request(client, **parametrs)
print(a)

It shows this error message: AttributeError: 'OperationProxy' object has no attribute 'input' . How to identify which attributes has OperationProxy. How to depub OperationProxy bodyor attributes list