modelcards and tensorboard are optional

setup.py

@@ -161,10 +161,11 @@ extras = {}
 extras = {}
 extras["quality"] = ["black ~= 22.0", "isort >= 5.5.4", "flake8 >= 3.8.3"]
 extras["docs"] = []
+extras["training"] = ["tensorboard", "modelcards"]
 extras["test"] = [
     "pytest",
 ]
-extras["dev"] = extras["quality"] + extras["test"]
+extras["dev"] = extras["quality"] + extras["test"] + extras["training"]
 
 install_requires = [
     deps["filelock"],
@@ -174,8 +175,6 @@ install_requires = [
     deps["requests"],
     deps["torch"],
     deps["Pillow"],
-    deps["tensorboard"],
-    deps["modelcards"],
 ]
 
 setup(

src/diffusers/hub_utils.py

@@ -21,7 +21,11 @@ from typing import Optional
 
 from diffusers import DiffusionPipeline
 from huggingface_hub import HfFolder, Repository, whoami
-from modelcards import CardData, ModelCard
+from utils import is_modelcards_available
+
+
+if is_modelcards_available():
+    from modelcards import CardData, ModelCard
 
 from .utils import logging
 
@@ -147,6 +151,12 @@ def push_to_hub(
 
 
 def create_model_card(args, model_name):
+    if not is_modelcards_available:
+        raise ValueError(
+            "Please make sure to have `modelcards` installed when using the `create_model_card` function. You can"
+            " install the package with `pip install modelcards`."
+        )
+
     if hasattr(args, "local_rank") and args.local_rank not in [-1, 0]:
         return
 

src/diffusers/utils/__init__.py

@@ -61,6 +61,14 @@ except importlib_metadata.PackageNotFoundError:
     _unidecode_available = False
 
 
+_modelcards_available = importlib.util.find_spec("modelcards") is not None
+try:
+    _modelcards_version = importlib_metadata.version("modelcards")
+    logger.debug(f"Successfully imported modelcards version {_modelcards_version}")
+except importlib_metadata.PackageNotFoundError:
+    _modelcards_available = False
+
+
 def is_transformers_available():
     return _transformers_available
 
@@ -73,6 +81,10 @@ def is_unidecode_available():
     return _unidecode_available
 
 
+def is_modelcards_available():
+    return _modelcards_available
+
+
 class RepositoryNotFoundError(HTTPError):
     """
     Raised when trying to access a hf.co URL with an invalid repository name, or with a private repo name the user does