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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 run_command( host, command, username=None, key_path=None, noisy=True ):
 """ Run a command via SSH, proxied through the mesos master :param host: host or IP of the machine to execute the command on :type host: str :param command: the command to execute :type command: str :param username: SSH username :type username: str :param key_path: path to the SSH private key to use for SSH authentication :type key_path: str :return: True if successful, False otherwise :rtype: bool :return: Output of command :rtype: string """

    
    with HostSession(host, username, key_path, noisy) as s:
        if noisy:
            print("\n{}{} $ {}\n".format(shakedown.fchr('>>'), host, command))
        s.run(command)
    
    ec, output = s.get_result()
    return ec == 0, output