diff --git a/xone/chart.py b/xone/chart.py
index e4a0559..90f2dd3 100644
--- a/xone/chart.py
+++ b/xone/chart.py
@@ -1,12 +1,16 @@
 import pandas as pd
 
+from typing import Union
 from xone import utils
 from matplotlib import pyplot as plt
 
 
 def plot_ts(
-        data: (pd.Series, pd.DataFrame), fld='close',
-        tz=None, vline=None, **kwargs
+        data: Union[pd.Series, pd.DataFrame],
+        fld='close',
+        tz=None,
+        vline=None,
+        **kwargs,
 ):
     """
     Time series data plots
@@ -229,7 +233,7 @@ def add_lines(
     return axes
 
 
-def xticks(data: (pd.Series, pd.DataFrame), max_cnt=8) -> pd.DataFrame:
+def xticks(data: Union[pd.Series, pd.DataFrame], max_cnt=8) -> pd.DataFrame:
     """
     Get x-ticks for intraday data
 
@@ -273,7 +277,7 @@ def xticks(data: (pd.Series, pd.DataFrame), max_cnt=8) -> pd.DataFrame:
     )
 
 
-def intraday(data: (pd.Series, pd.DataFrame), max_cnt=8, **kwargs):
+def intraday(data: Union[pd.Series, pd.DataFrame], max_cnt=8, **kwargs):
     """
     Plot intraday data
 
diff --git a/xone/utils.py b/xone/utils.py
index 93dfbe3..e4bab1c 100644
--- a/xone/utils.py
+++ b/xone/utils.py
@@ -7,9 +7,17 @@
 import inspect
 import sys
 
+from typing import Union
 from xone import __version__
 
-__all__ = ['__version__']
+__all__ = [
+    '__version__',
+    'tolist',
+    'fmt_dt',
+    'trade_day',
+    'cur_time',
+    'align_data',
+]
 
 DEFAULT_TZ = pytz.FixedOffset(-time.timezone / 60)
 
@@ -414,7 +422,7 @@ def func_kwarg(func, **kwargs) -> dict:
     return {k: v for k, v in kwargs.items() if k in kind}
 
 
-def perf(data: (pd.DataFrame, pd.Series)) -> (pd.DataFrame, pd.Series):
+def perf(data: Union[pd.DataFrame, pd.Series]) -> Union[pd.DataFrame, pd.Series]:
     """
     Price performance based at 100