Visual Process API error

Hello,

I'm trying to use Monarch Visual Process Designer API from Python. Login request returns success, but visualprocess/start  returns an error. Below is a script and the output. What am I doing wrong?

Thank you!

monarch_rest_api.py
import requests

url = "http://us1-monarch1/MSAdmin/api"
login_info = {"Username":"test_login", "Password":"test_password"}
jobname = "Test Job"

resp = requests.post(url + "/login", json = login_info)
print ("Login: ", resp.status_code)

resp = requests.post(url + "/v1/visualprocesses/start", data=jobname, headers={'Content-Type':'application/json'})
print ("Start: ", resp.status_code)
print (resp.json())

Output
H:\python>python monarch_rest_api.py
Login: 200
Start: 500
{'Message': 'An error has occurred.'}

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Leonid Shteyngardt
App Dev Manager
Canaccord Genuity Inc.
New York NY
(212) 389-8176
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