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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_seq_cluster(pdb_id_chain):
 """Get the sequence cluster of a PDB ID plus a pdb_id plus a chain, Parameters pdb_id_chain : string A string denoting a 4 character PDB ID plus a one character chain offset with a dot: XXXX.X, as in 2F5N.A Returns ------- out : dict A dictionary containing the sequence cluster associated with the PDB entry and chain Examples -------- [{'@name': '4PD2.A', '@rank': '1'}, {'@name': '3U6P.A', '@rank': '2'}, {'@name': '4PCZ.A', '@rank': '3'}, {'@name': '3GPU.A', '@rank': '4'}, {'@name': '3JR5.A', '@rank': '5'}, {'@name': '3SAU.A', '@rank': '6'}, {'@name': '3GQ4.A', '@rank': '7'}, {'@name': '1R2Z.A', '@rank': '8'}, {'@name': '3U6E.A', '@rank': '9'}, {'@name': '2XZF.A', '@rank': '10'}] """


    url_root = 'http://www.rcsb.org/pdb/rest/sequenceCluster?structureId='
    out = get_info(pdb_id_chain, url_root = url_root)
    out = to_dict(out)
    return remove_at_sign(out['sequenceCluster'])