from urllib import urlencode
import pycurl
import pprint
import json
from io import BytesIO

data = BytesIO()
c = pycurl.Curl()
c.setopt(c.URL, 'https://partners.com/api/v2/login')

post_data = {'username': 'user', 'password': 'pass'}

postfields = urlencode(post_data)

c.setopt(c.POSTFIELDS, postfields)

c.setopt(c.WRITEFUNCTION, data.write)
c.perform()
dictionary = json.loads(data.getvalue())
pprint.pprint(dictionary["access_token"]) #Con Comillas
print(dictionary["access_token"])         #Sin Comillas

c.setopt(c.URL, 'https://partners.com/api/v2/traffic-channels')

post_data = {"trafficChannel":{"name":"martin","status":0,"billedEvent":"ai","env":"desktop","dealType":"fixed_price","cost":2,"floor":3,"optimizeAllAdSources":"true","optimizeFor":"fillRate","publisher":"5a01fee6cf4b4c000288e254"}}

postfields = urlencode(post_data)

c.setopt(c.POSTFIELDS, postfields)
c.perform()

curl 'https://partners.com/api/v2/login' -d 'username=johnSmith&password=mYpassw0rd'
Response:
{
    "access_token":"SKbWW6YEtCdkxOO6g7teO3JMKQNSTQa9I2V00T6kGSX7BWVrMPbJsCaKNJ2SuAoyHxqdr8CqpA1v193mbbwi86MCCKpx4sr55ziF",
    "token_type":"bearer",
    "user_id":"aCdsvU98ks5jFIxiKDGsW7G"
    }
}

curl 'https://partners.com/api/v2/traffic-channels'
-H 'Authorization: Bearer SKbWW6YEtCdkxOO6g7teO3JMKQNSTQa9I2V00T6kGSX7BWVrMPbJsCaKNJ2SuAoyHxqdr8CqpA1v193mbbwi86MCCKpx4sr55ziF'
-d '{"trafficChannel":{"name":"tc2","status":0,"billedEvent":"ai","env":"desktop","dealType":"fixed_price","optimizeAllAdSources":false,"optimizeFor":"ecpm","useCache":false,"publisher":"1fi6cfjz3l23cmr67t4u39m"}}'
Response:
{
   "trafficChannel":{
      "id":"3kuop6vuo1qf46kszixf2me",
      "name":"tc2",
      "createdOn":"2017-04-04T09:57:58.463832363Z",
      "lastModified":"2017-04-04T09:57:58.463828293Z",
      "createdBy":"fAq04U17V6YCYkHBGniyAh8",
      "modifiedBy":"fAq04U17V6YCYkHBGniyAh8",
      "org":"b04q1yxgsk6udnrfng7qf05",
      "dealType":"fixed_price",
      "billedEvent":"ai",
      "publisher":"1fi6cfjz3l23cmr67t4u39m",
      "optimizeFor":"ecpm",
      "dealTypeExceptions":null,
      "env":"desktop",
      "waterfalls":0
   }
}