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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_all_clusters_sites():
 """Get all the cluster of all the sites. Returns: dict corresponding to the mapping cluster uid to python-grid5000 site """

    result = {}
    gk = get_api_client()
    sites = gk.sites.list()
    for site in sites:
        clusters = site.clusters.list()
        result.update({c.uid: site.uid for c in clusters})
    return result