def __init__(self, graph, clusters=None):
    'Creates a cover object for a given graph.\n\n        @param graph: the graph that will be associated to the cover\n        @param clusters: the list of clusters. If C{None}, it is assumed\n          that there is only a single cluster that covers the whole graph.\n        '
    if (clusters is None):
        clusters = [range(graph.vcount())]
    Cover.__init__(self, clusters, n=graph.vcount())
    if (self._n > graph.vcount()):
        raise ValueError('cluster list contains vertex ID larger than the number of vertices in the graph')
    self._graph = graph
Creates a cover object for a given graph.

@param graph: the graph that will be associated to the cover
@param clusters: the list of clusters. If C{None}, it is assumed
  that there is only a single cluster that covers the whole graph.
def __init__(self, graph, clusters=None):
    'Creates a cover object for a given graph.\n\n        @param graph: the graph that will be associated to the cover\n        @param clusters: the list of clusters. If C{None}, it is assumed\n          that there is only a single cluster that covers the whole graph.\n        '
    if (clusters is None):
        clusters = [range(graph.vcount())]
    Cover.__init__(self, clusters, n=graph.vcount())
    if (self._n > graph.vcount()):
        raise ValueError('cluster list contains vertex ID larger than the number of vertices in the graph')
    self._graph = graph