diff --git a/focal_loss.py b/focal_loss.py
index 28b9e3e..b0a4175 100644
--- a/focal_loss.py
+++ b/focal_loss.py
@@ -51,6 +51,7 @@ def __init__(self,
     def __repr__(self):
         arg_keys = ['alpha', 'gamma', 'ignore_index', 'reduction']
         arg_vals = [self.__dict__[k] for k in arg_keys]
+        arg_vals = [f'\'{v}\'' if isinstance(v, str) else v for v in arg_vals]
         arg_strs = [f'{k}={v}' for k, v in zip(arg_keys, arg_vals)]
         arg_str = ', '.join(arg_strs)
         return f'{type(self).__name__}({arg_str})'