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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_clusters_interfaces(clusters, extra_cond=lambda nic: True):
 """ Returns for each cluster the available cluster interfaces Args: clusters (str):
 list of the clusters extra_cond (lambda):
 extra predicate to filter network card retrieved from the API. E.g lambda nic: not nic['mounted'] will retrieve all the usable network cards that are not mounted by default. Returns: dict of cluster with their associated nic names Examples: .. code-block:: python # pseudo code actual = get_clusters_interfaces(["paravance"]) expected = {"paravance": ["eth0", "eth1"]} assertDictEquals(expected, actual) """


    interfaces = {}
    for cluster in clusters:
        nics = get_cluster_interfaces(cluster, extra_cond=extra_cond)
        interfaces.setdefault(cluster, nics)

    return interfaces