eman
diff --git a/‎influxdb/_dataframe_client.py
Lines changed: 13 additions & 7 deletions b/‎influxdb/_dataframe_client.py
Lines changed: 13 additions & 7 deletions
diff --git a/‎3-3Lines changed: 3 additions & 3 deletions b/‎3-3Lines changed: 3 additions & 3 deletions
@@ -44,8 +44,8 @@ def write_points(self,
                      dataframe,
                      measurement,
                      tags=None,
-                     tag_columns=[],
-                     field_columns=[],
+                     tag_columns=None,
+                     field_columns=None,
                      time_precision=None,
                      database=None,
                      retention_policy=None,
@@ -72,6 +72,10 @@ def write_points(self,
             figures for float and all significant figures for int datatypes.
 
         """
+        if tag_columns is None:
+            tag_columns = []
+        if field_columns is None:
+            field_columns = []
         if batch_size:
             number_batches = int(math.ceil(len(dataframe) / float(batch_size)))
             for batch in range(number_batches):
@@ -166,8 +170,8 @@ def _convert_dataframe_to_json(self,
                                    dataframe,
                                    measurement,
                                    tags=None,
-                                   tag_columns=[],
-                                   field_columns=[],
+                                   tag_columns=None,
+                                   field_columns=None,
                                    time_precision=None):
 
         if not isinstance(dataframe, pd.DataFrame):
@@ -221,9 +225,9 @@ def _convert_dataframe_to_json(self,
     def _convert_dataframe_to_lines(self,
                                     dataframe,
                                     measurement,
-                                    field_columns=[],
-                                    tag_columns=[],
-                                    global_tags={},
+                                    field_columns=None,
+                                    tag_columns=None,
+                                    global_tags=None,
                                     time_precision=None,
                                     numeric_precision=None):
 
@@ -242,6 +246,8 @@ def _convert_dataframe_to_lines(self,
             field_columns = []
         if tag_columns is None:
             tag_columns = []
+        if global_tags is None:
+            global_tags = {}
 
         # Make sure field_columns and tag_columns are lists
         field_columns = list(field_columns) if list(field_columns) else []
 
@@ -131,8 +131,8 @@ def _port(self):
     def _get_port(self):
         return self.__port
 
-    @staticmethod
-    def from_DSN(dsn, **kwargs):
+    @classmethod
+    def from_DSN(cls, dsn, **kwargs):
         """Return an instance of :class:`~.InfluxDBClient` from the provided
         data source name. Supported schemes are "influxdb", "https+influxdb"
         and "udp+influxdb". Parameters for the :class:`~.InfluxDBClient`
@@ -169,7 +169,7 @@ def from_DSN(dsn, **kwargs):
         init_args['port'] = port
         init_args.update(kwargs)
 
-        return InfluxDBClient(**init_args)
+        return cls(**init_args)
 
     def switch_database(self, database):
         """Change the client's database.