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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 is_connected(T, directed=True):
 r"""Check connectivity of the transition matrix. Return true, if the input matrix is completely connected, effectively checking if the number of connected components equals one. Parameters T : scipy.sparse matrix Transition matrix directed : bool, optional Whether to compute connected components for a directed or undirected graph. Default is True. Returns ------- connected : boolean, returning true only if T is connected. """

    nc = connected_components(T, directed=directed, connection='strong', \
                              return_labels=False)
    return nc == 1