_ETREE_EXCEPTIONS = (ParseError, AttributeError, ValueError, TypeError)
else:
    _ETREE_EXCEPTIONS = (SyntaxError, AttributeError, ValueError, TypeError)

_STS_NS = {'sts': 'https://sts.amazonaws.com/doc/2011-06-15/'}


class STSElement(object):
    """STS aware XML parsing class. Wraps a root element name and
    cElementTree.Element instance. Provides STS namespace aware parsing
    functions.

    """

            query = {}
            query['Action'] = 'AssumeRoleWithClientGrants'
            query['Token'] = creds['access_token']
            query['DurationSeconds'] = creds['expires_in']
            query['Version'] = '2011-06-15'

            query_components = []
            for key in query:
                if query[key] is not None:
                    query_components.append("%s=%s" % (key, query[key]))