diff --git a/binarycpython/utils/population_extensions/dataIO.py b/binarycpython/utils/population_extensions/dataIO.py
index ce459647bcfe2b4576ac7cd28a41464cccd2784e..ae943a0c4dd06459eb260e3ada5d00993e7743ff 100644
--- a/binarycpython/utils/population_extensions/dataIO.py
+++ b/binarycpython/utils/population_extensions/dataIO.py
@@ -410,7 +410,7 @@ class dataIO:
 
         Also, make sure that in this export there are the basic parameters
         like m1,m2,sep, orb-per, ecc, probability etc.
-
+        TODO: this function can probably be cleaned a bit and can rely on the other startup and clean up functions (see population_class)
         On default this will write to the datadir, if it exists
 
         Args:
diff --git a/binarycpython/utils/population_extensions/sampling_variables.py b/binarycpython/utils/population_extensions/sampling_variables.py
index f8c995d81c04f9fbd461997d8d070c26b3fabc1e..6e4cc8e040bac5ac2cb94a00432ac4ee2675f2e0 100644
--- a/binarycpython/utils/population_extensions/sampling_variables.py
+++ b/binarycpython/utils/population_extensions/sampling_variables.py
@@ -147,6 +147,7 @@ class sampling_variables:
         bottomcode: Union[str, None] = None,
         condition: Union[str, None] = None,
         dry_parallel: Union[bool, None] = False,
+        dependency_variables: Union[list, None] = None,
     ) -> None:
         """
         Function to add sampling variables to the grid_options.
@@ -248,6 +249,9 @@ class sampling_variables:
 
             bottomcode:
                 Code added at the very bottom of the block.
+
+            dependency_variables:
+                TODO: describe
         """
 
         # check parameters
@@ -278,6 +282,7 @@ class sampling_variables:
             "bottomcode": bottomcode,
             "sampling_variable_number": len(self.grid_options["_sampling_variables"]),
             "dry_parallel": dry_parallel,
+            "dependency_variables": dependency_variables,
         }
 
         # Check for gridtype input