PythonからGoogle APIsを利用する際のOAuth2エラーの対処方法 ref: http://qiita.com/kndt84/items/4c2b16000b0ce32b6bcf

bq-access.py

import json
from httplib2 import Http
from oauth2client.client import SignedJwtAssertionCredentials
from apiclient.discovery import build

SERVICE_ACCOUNT_EMAIL = '**********@developer.gserviceaccount.com'
PROJECT_NUMBER = '**********'
KEYFILE='******************.p12'

with open(KEYFILE) as f:
  private_key = f.read()

credentials = SignedJwtAssertionCredentials(
    SERVICE_ACCOUNT_EMAIL, private_key,
    'https://www.googleapis.com/auth/bigquery')

http = Http()
credentials.authorize(http)

service = build('bigquery', 'v2', http=http)
response = service.datasets().list(projectId='************').execute()

print response

file0.txt

ssl.SSLError: [Errno 185090050] _ssl.c:343: error:0B084002:x509 certificate routines:X509_load_cert_crl_file:system lib

file2.txt

> cd /Library/Python/2.7/site-packages/httplib2-0.9.1-py2.7.egg/httplib2/
> ls -l cacerts.txt
-rw-r-----  1 root  wheel  134862  7 13 18:36 cacerts.txt

file3.txt

> sudo chmod 644 cacerts.txt