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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 bash_rule(bash, hostnames):
 """ Cluster rule to process bash and hostname info ``bash`` and ``hostnames`` are Pandas DataFrames for the facts collected for each host in the cluster. See https://pandas.pydata.org/pandas-docs/stable/api.html#dataframe for information on available attributes and methods. Arguments: bash (pandas.DataFrame):
 Includes facts from ``bash_version`` fact with columns "name" and "version" and one row per host in the cluster. hostnames (pandas.DataFrame):
 Includes facts from ``get_hostname`` fact with column "hostname" and one row per host in the cluster. """

    if isinstance(bash, dict):
        return make_fail('bash_rule',
                         error_message="Run this rule with a cluster archive")

    return make_pass('bash_rule', bash=bash, hostname=hostnames)