Added default

Author: TomAugspurger

pandas/core/arrays/categorical.py

@@ -490,7 +490,7 @@ def base(self):
 
     @classmethod
     def _from_inferred_categories(cls, inferred_categories, inferred_codes,
-                                  dtype, true_values):
+                                  dtype, true_values=None):
         """Construct a Categorical from inferred values
 
         For inferred categories (`dtype` is None) the categories are sorted.
@@ -503,7 +503,9 @@ def _from_inferred_categories(cls, inferred_categories, inferred_codes,
         inferred_categories : Index
         inferred_codes : Index
         dtype : CategoricalDtype or 'category'
-        true_values : list of bytes
+        true_values : list of bytes, optional
+            Uses the default `true_values` defined in parsers.pyx
+            by default.
 
         Returns
         -------