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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 _urls(self):
 """Constructs the URLconf for Horizon from registered Dashboards."""

        urlpatterns = self._get_default_urlpatterns()
        self._autodiscover()

        # Discover each dashboard's panels.
        for dash in self._registry.values():
            dash._autodiscover()

        # Load the plugin-based panel configuration
        self._load_panel_customization()

        # Allow for override modules
        if self._conf.get("customization_module", None):
            customization_module = self._conf["customization_module"]
            bits = customization_module.split('.')
            mod_name = bits.pop()
            package = '.'.join(bits)
            mod = import_module(package)
            try:
                before_import_registry = copy.copy(self._registry)
                import_module('%s.%s' % (package, mod_name))
            except Exception:
                self._registry = before_import_registry
                if module_has_submodule(mod, mod_name):
                    raise

        # Compile the dynamic urlconf.
        for dash in self._registry.values():
            urlpatterns.append(url(r'^%s/' % dash.slug,
                                   _wrapped_include(dash._decorated_urls)))

        # Return the three arguments to django.conf.urls.include
        return urlpatterns, self.namespace, self.slug