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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 allele_clusters(dists, t=0.025):
 """Flat clusters from distance matrix Args: dists (numpy.array):
 pdist distance matrix t (float):
 fcluster (tree cutting) distance threshold Returns: dict of lists: cluster number to list of indices of distances in cluster """

    clusters = fcluster(linkage(dists), 0.025, criterion='distance')
    cluster_idx = defaultdict(list)
    for idx, cl in enumerate(clusters):
        cluster_idx[cl].append(idx)
    return cluster_idx