diff --git a/docs/source/c8_changes.rst b/docs/source/c8_changes.rst
index 7bebf89c910244e32c986db1ca3a2e621eefc189..1f203f64afb3533ae0266e2d1791281397ff91a7 100644
--- a/docs/source/c8_changes.rst
+++ b/docs/source/c8_changes.rst
@@ -28,11 +28,12 @@ Change list
 
         .. code-block:: python
 
-            import os.path
+            import os
 
             import numpy as np
-            from astropy.io import fits
+            import numpy.typing as npt
             from astropy import table
+            from astropy.io import fits
             from csst_common.status import CsstStatus, CsstResult
 
 
@@ -40,23 +41,26 @@ Change list
                 return fits.getdata(file_path)
 
 
-            def _do_step_one(data: np.ndarray) -> np.ndarray:
+            def _do_step_one(data: npt.NDArray) -> npt.NDArray:
                 reduced_data = np.fliplr(data)
                 return reduced_data
 
 
-            def _do_step_two(data: np.ndarray) -> np.ndarray:
+            def _do_step_two(data: npt.NDArray) -> npt.NDArray:
                 reduced_data = np.flipud(data)
                 return reduced_data
 
 
-            def _do_step_three(data: np.ndarray, rc="/path/to/catalog") -> np.ndarray:
+            def _do_step_three(data: npt.NDArray, rc: str = "/path/to/catalog") -> npt.NDArray:
                 trc = table.Table.read(rc)
                 return data + np.mean(trc["ra"]) + np.mean(trc["dec"])
 
 
             def base_msc_l1_mbi_image_distortion(
-                input_file, output_file, rc: str = "/path/to/gaia_dr3.fits", **kwargs
+                input_file: str,
+                output_file: str,
+                rc: str = "/path/to/gaia_dr3.fits",
+                **kwargs
             ) -> CsstResult:
                 """your docstring here"""
                 # read data
@@ -71,11 +75,17 @@ Change list
                 assert os.path.exists(output_file)
                 # construct CsstResult
                 result = CsstResult(
-                    status=CsstStatus.PERFECT, file_list=[output_file, "an additional output file"]
+                    status=CsstStatus.PERFECT,
+                    file_list=[
+                        output_file,
+                        "/path/to/result1.fits",
+                        "/path/to/result2.fits",
+                    ],
                 )
                 return result
 
 
+
 导入模块
 ---------