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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 list_repos(root=None, **kwargs):
    '''
    Lists all repos.

    root
        operate on a different root directory.

    CLI Example:

    .. code-block:: bash

       salt '*' pkg.list_repos
    '''
    repos_cfg = _get_configured_repos(root=root)
    all_repos = {}
    for alias in repos_cfg.sections():
        all_repos[alias] = _get_repo_info(alias, repos_cfg=repos_cfg, root=root)

    return all_repos