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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 _accumulate_remotes(synapse_parent_id, syn):
 """Retrieve references to all remote directories and files. """

    remotes = {}
    s_base_folder = syn.get(synapse_parent_id)
    for (s_dirpath, s_dirpath_id), _, s_filenames in synapseutils.walk(syn, synapse_parent_id):
        remotes[s_dirpath] = s_dirpath_id
        if s_filenames:
            for s_filename, s_filename_id in s_filenames:
                remotes[os.path.join(s_dirpath, s_filename)] = s_filename_id
    return s_base_folder, remotes