Merge pull request #37 from Pennycook/repr-string

Fix incorrect usage of _representation_string

Author: Pennycook

codebasin/preprocessor.py

@@ -626,7 +626,7 @@ def to_json(self, assoc):
         return parent_json
 
     def __repr__(self):
-        return _representation_string(self, attrs="filename")
+        return _representation_string(self, attrs=["filename"])
 
     def __str__(self):
         return f"{str(self.filename)}; Hash: {str(self.file_hash)}"