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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 ssh_session(key_filename, username, ip_address, *cli):
 """ opens a ssh shell to the host """

    local('ssh -t -i %s %s@%s %s' % (key_filename,
                                     username,
                                     ip_address,
                                     "".join(chain.from_iterable(cli))))