import json

from oauthlib.common import to_unicode

def mailchimp_compliance_fix(session):
    def _null_scope(r):
        token = json.loads(r.text)
        if 'scope' in token and token['scope'] is None:
            token.pop('scope')
        r._content = to_unicode(json.dumps(token)).encode('utf-8')
        return r

    def _non_zero_expiration(r):
        token = json.loads(r.text)
        if 'expires_in' in token and token['expires_in'] == 0:
            token['expires_in'] = 3600
        r._content = to_unicode(json.dumps(token)).encode('utf-8')
        return r

    session.register_compliance_hook('access_token_response', _null_scope)
    session.register_compliance_hook('access_token_response', _non_zero_expiration)
    return session