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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 do(ruby, command, runas=None, cwd=None, env=None):  # pylint: disable=C0103
    '''
    Execute a command in an RVM controlled environment.

    ruby
        Which ruby to use

    command
        The rvm command to execute

    runas
        The user under which to run rvm. If not specified, then rvm will be run
        as the user under which Salt is running.

    cwd
        The directory from which to run the rvm command. Defaults to the user's
        home directory.

    CLI Example:

    .. code-block:: bash

        salt '*' rvm.do 2.0.0 <command>
    '''
    try:
        command = salt.utils.args.shlex_split(command)
    except AttributeError:
        command = salt.utils.args.shlex_split(six.text_type(command))
    return _rvm_do(ruby, command, runas=runas, cwd=cwd, env=env)