How to decode STS message from AWS using boto, helpful to debug permissions issues with IAM policies

sts-console.py

>>> import json
>>> import pprint
>>> from boto.sts import STSConnection
>>> s = STSConnection()
>>> d = s.decode_authorization_message('48hdmxfrx3...41DFkQ') # replace with your own string
>>> pprint.pprint(json.loads(d.decoded_message), indent=4)
{   u'allowed': False,
    u'context': {   u'action': u'iam:PassRole',
                    u'conditions': {   u'items': []},
                    u'principal': {   u'arn': u'arn:aws:iam::334918212912:user/staging-bouncer',
                                      u'id': u'AIDAIA6EK27IQ5JAHLLRM',
                                      u'name': u'staging-bouncer'},
                    u'resource': u'arn:aws:iam::334918212912:role/StagingScanworkerpolicy'},
    u'explicitDeny': False,
    u'failures': {   u'items': []},
    u'matchedStatements': {   u'items': []}}