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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 install_pyenv(name, user=None):
    '''
    Install pyenv if not installed. Allows you to require pyenv be installed
    prior to installing the plugins. Useful if you want to install pyenv
    plugins via the git or file modules and need them installed before
    installing any rubies.

    Use the pyenv.root configuration option to set the path for pyenv if you
    want a system wide install that is not in a user home dir.

    user: None
        The user to run pyenv as.
    '''
    ret = {'name': name, 'result': None, 'comment': '', 'changes': {}}

    if __opts__['test']:
        ret['comment'] = 'pyenv is set to be installed'
        return ret

    return _check_and_install_python(ret, user)