add private module to create model object for library api

opendbm/api_lib/facial_activity/_asymmetry.py

@@ -0,0 +1,20 @@
+import tempfile
+
+from opendbm.api_lib.model import VideoModel
+from opendbm.dbm_lib import run_face_asymmetry
+
+
+class Asymmetry(VideoModel):
+    def __init__(self):
+        super().__init__()
+        self._params = [
+            "fac_asymmaskmouth",
+            "fac_asymmaskeye",
+            "fac_asymmaskeyebrow",
+            "fac_asymmaskcom",
+        ]
+
+    def _fit_transform(self, path):
+        return run_face_asymmetry(
+            path, f"{tempfile.gettempdir()}/", self.r_config, save=False
+        )