After deploying getting error 502 while generating forecast in Azure Ml through Code

Question

Hi,
After doing the deployment task, i am not able to generate the forecast through code pipeline of Azure Ml.
this is my run.py file:

def run(df, url, api_key):
allowSelfSignedHttps(True)
if api_key == 'uu':
api_key = ''
data = []
for index, row in list(df.iterrows()):
data.append(dict(row))

data = {

    "data": data
}

body = str.encode(json.dumps(data))
headers = {'Content-Type': 'application/json',
           'Authorization': ('Bearer ' + api_key)}

req = urllib.request.Request(url, body, headers)
print(url, api_key)
try:
    response = urllib.request.urlopen(req)
    result = response.read()
    print(result)
except urllib.error.HTTPError as error:
    print("The request failed with status code: " + str(error.code))

    # Print the headers - they include the requert ID and the timestamp, which are useful for debugging the failure
    print(error.info())
    # print(json.loads(error.read().decode("utf8", 'ignore')))

data = json.loads(json.load(response))
df= pd.json_normalize(data[result])
data = data.get('forecast', None)
return data

Error: 502