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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 datasetsBM(host=biomart_host):
 """ Lists BioMart datasets. :param host: address of the host server, default='http://www.ensembl.org/biomart' :returns: nothing """

    stdout_ = sys.stdout #Keep track of the previous value.
    stream = StringIO()
    sys.stdout = stream   
    server = BiomartServer(biomart_host)
    server.show_datasets()
    sys.stdout = stdout_ # restore the previous stdout.
    variable = stream.getvalue() 
    v=variable.replace("{"," ") 
    v=v.replace("}"," ") 
    v=v.replace(": ","\t")
    print(v)