'Describes instance types.
:param      filters: The filters so that the list returned includes
information for instance types only
:type       filters: ``dict``
:return:    A instance types list
:rtype:     ``list``'

def ex_describe_instance_types(self, filters=None):

    params = {'Action': 'DescribeInstanceTypes'}
    if filters:
        params.update(self._build_filters(filters))
    response = self.connection.request(self.path, params=params, method='GET').object
    instance_types = self._to_instance_types(response)
    return instance_types
