fix retainDataByFacetValue issue (#3)

Author: pochedls

xsearch/__init__.py

@@ -12,7 +12,7 @@
 import os
 
 # version
-__version__ = "0.0.6"
+__version__ = "0.0.7"
 
 # since this software is installed centrally and may be updated
 # this section of code stores the xsearch version in a hidden

xsearch/search.py

@@ -37,11 +37,12 @@ def retainDataByFacetValue(db, facet, value):
         values dict: dictionary with all items dropped, except
                      those matching the facet-value pairing
     """
-    keyList = list(db.keys())
+    db_copy = db.copy()
+    keyList = list(db_copy.keys())
     for key in keyList:
-        if db[key][facet] != value:
-            db.pop(key)
-    return db
+        if db_copy[key][facet] != value:
+            db_copy.pop(key)
+    return db_copy
 
 
 def natural_sort(l):