diff --git a/onnxmltools/convert/lightgbm/_parse.py b/onnxmltools/convert/lightgbm/_parse.py
index e527faf7..d711abe0 100644
--- a/onnxmltools/convert/lightgbm/_parse.py
+++ b/onnxmltools/convert/lightgbm/_parse.py
@@ -27,9 +27,7 @@ def __init__(self, booster):
         if (_model_dict['objective'].startswith('binary') or
                 _model_dict['objective'].startswith('multiclass')):
             self.operator_name = 'LgbmClassifier'
-        elif (_model_dict['objective'].startswith('regression') or
-                _model_dict['objective'].startswith('poisson') or
-                _model_dict['objective'].startswith('gamma')):
+        elif _model_dict['objective'].startswith(('regression', 'poisson', 'gamma')):
             self.operator_name = 'LgbmRegressor'
         else:
             # Other objectives are not supported.
diff --git a/onnxmltools/convert/lightgbm/operator_converters/LightGbm.py b/onnxmltools/convert/lightgbm/operator_converters/LightGbm.py
index c2ad360c..242c2c1d 100644
--- a/onnxmltools/convert/lightgbm/operator_converters/LightGbm.py
+++ b/onnxmltools/convert/lightgbm/operator_converters/LightGbm.py
@@ -234,7 +234,7 @@ def convert_lightgbm(scope, operator, container):
         n_classes = 1  # Regressor has only one output variable
         attrs['post_transform'] = 'NONE'
         attrs['n_targets'] = n_classes
-    elif gbm_text['objective'].startswith('poisson') or gbm_text['objective'].startswith('gamma'):
+    elif gbm_text['objective'].startswith(('poisson', 'gamma')):
         n_classes = 1  # Regressor has only one output variable
         attrs['n_targets'] = n_classes
         # 'Exp' is not a supported post_transform value in the ONNX spec yet,