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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 reinstall_ruby(ruby, runas=None, env=None):
    '''
    Reinstall a ruby implementation

    ruby
        The version of ruby to reinstall

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

    CLI Example:

    .. code-block:: bash

        salt '*' rvm.reinstall_ruby 1.9.3-p385
    '''
    return _rvm(['reinstall', ruby], runas=runas, env=env)