objectif

Récupérer la version d’une distribution installée (fallback si absente).

code minimal

try:
    from importlib.metadata import version, PackageNotFoundError
except ImportError:
    from importlib_metadata import version, PackageNotFoundError  # backport

try:
    v = version("pip")
    print(isinstance(v, str))  # attendu: True (si pip présent)
except PackageNotFoundError:
    print(True)  # attendu: True (fallback)

utilisation

from importlib import metadata
dists = list(metadata.distributions())
print(isinstance(dists, list))

variante(s) utile(s)

from importlib import metadata
print(isinstance(metadata.packages_distributions(), dict))

notes

• Préférez importlib.metadata (stdlib 3.8+), sinon backport importlib-metadata.
• Attention: nom de distrib != nom de module (ex: “Pillow” -> “PIL”).