from typing import Dict
from typing import List


def get_available_languages(localisation: Dict) -> List[str]:
    """Get list of languages that are available for outputting human readable
    procedure descriptions.

    Args:
        Dict: Localisation collection, e.g. ``PlatformClass().localisation``

    Returns:
        List[str]: List of language codes, e.g. ['en', 'zh']
    """
    available_languages = ['en']
    for _, human_readables in localisation.items():
        for language in human_readables:
            if language not in available_languages:
                available_languages.append(language)
    return available_languages