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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_endpoint(brain_or_object, default=DEFAULT_ENDPOINT):
 """Calculate the endpoint for this object :param brain_or_object: A single catalog brain or content object :type brain_or_object: ATContentType/DexterityContentType/CatalogBrain :returns: Endpoint for this object :rtype: string """

    portal_type = get_portal_type(brain_or_object)
    resource = portal_type_to_resource(portal_type)

    # Try to get the right namespaced endpoint
    endpoints = router.DefaultRouter.view_functions.keys()
    if resource in endpoints:
        return resource  # exact match
    endpoint_candidates = filter(lambda e: e.endswith(resource), endpoints)
    if len(endpoint_candidates) == 1:
        # only return the namespaced endpoint, if we have an exact match
        return endpoint_candidates[0]

    return default