init coordinates.py

csst_common/coordinates.py

+from astropy.wcs import WCS
+
+
+def transform_coordinate(
+    ra: float = 180.000,
+    dec: float = 0.0,
+    original_epoch: float = 2016.0,
+    target_epoch: float = 2020.0,
+) -> tuple[float, float]:
+    """Transform a coordinate from `original_epoch` to `target_epoch`."""
+    pass
+
+
+def transform_wcs(
+    wcs: WCS, original_epoch: float = 2016.0, target_epoch: float = 2020.0
+) -> WCS:
+    """Transform a wcs from `original_epoch` to `target_epoch`."""
+    pass