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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 RattributesBM(dataset,database,host=rbiomart_host):
 """ Lists BioMart attributes through a RPY2 connection. :param dataset: a dataset listed in RdatasetsBM() :param database: a database listed in RdatabasesBM() :param host: address of the host server, default='www.ensembl.org' :returns: nothing """

    biomaRt = importr("biomaRt")
    ensemblMart=biomaRt.useMart(database, host=rbiomart_host)
    ensembl=biomaRt.useDataset(dataset, mart=ensemblMart)
    print(biomaRt.listAttributes(ensembl))