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
    --------

    >>> sclust = get_seq_cluster('2F5N.A')
    >>> print(sclust['pdbChain'][:10])
    [{'@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'])
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
    --------

    >>> sclust = get_seq_cluster('2F5N.A')
    >>> print(sclust['pdbChain'][:10])
    [{'@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'}]