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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 register(self, prefix, viewset, base_name=None):
 """Add any registered route into a global API directory. If the prefix includes a path separator, store the URL in the directory under the first path segment. Otherwise, store it as-is. For example, if there are two registered prefixes, 'v1/users' and 'groups', `directory` will look liks: { 'v1': { 'users': { '_url': 'users-list' '_viewset': <class 'UserViewSet'> }, } 'groups': { '_url': 'groups-list' '_viewset': <class 'GroupViewSet'> } } """

        if base_name is None:
            base_name = prefix

        super(DynamicRouter, self).register(prefix, viewset, base_name)

        prefix_parts = prefix.split('/')
        if len(prefix_parts) > 1:
            prefix = prefix_parts[0]
            endpoint = '/'.join(prefix_parts[1:])
        else:
            endpoint = prefix
            prefix = None

        if prefix and prefix not in directory:
            current = directory[prefix] = {}
        else:
            current = directory.get(prefix, directory)

        list_name = self.routes[0].name
        url_name = list_name.format(basename=base_name)
        if endpoint not in current:
            current[endpoint] = {}
        current[endpoint]['_url'] = url_name
        current[endpoint]['_viewset'] = viewset