def get_instances_by_tags(self, tags):
    """
    Get all instances tagged with the tags given in arguments.

    :param boto.ec2.EC2Connection self:
        Current connection.
    :param dict tags:
        Dict of tags as strings (e.g : {'name': 'toto', 'env': 'prod'})

    :return: List of EC2Object Instance
    :rtype: list
    """
    return self.get_only_instances(filters={'tag:{}'.format(key): val for key, val in tags.items()})