diff --git a/funcat/func.py b/funcat/func.py
index aca5846..5bfffb9 100644
--- a/funcat/func.py
+++ b/funcat/func.py
@@ -20,7 +20,10 @@
 
 
 class OneArgumentSeries(NumericSeries):
-    func = talib.MA
+
+    @staticmethod
+    def func(*args, **kwargs):
+        return talib.MA(*args, **kwargs)
 
     def __init__(self, series, arg):
         if isinstance(series, NumericSeries):
@@ -37,21 +40,32 @@ def __init__(self, series, arg):
 
 class MovingAverageSeries(OneArgumentSeries):
     """http://www.tadoc.org/indicator/MA.htm"""
-    func = talib.MA
+
+    @staticmethod
+    def func(*args, **kwargs):
+        return talib.MA(*args, **kwargs)
 
 
 class WeightedMovingAverageSeries(OneArgumentSeries):
     """http://www.tadoc.org/indicator/WMA.htm"""
-    func = talib.WMA
+
+    @staticmethod
+    def func(*args, **kwargs):
+        return talib.WMA(*args, **kwargs)
 
 
 class ExponentialMovingAverageSeries(OneArgumentSeries):
     """http://www.fmlabs.com/reference/default.htm?url=ExpMA.htm"""
-    func = talib.EMA
+
+    @staticmethod
+    def func(*args, **kwargs):
+        return talib.EMA(*args, **kwargs)
 
 
 class StdSeries(OneArgumentSeries):
-    func = talib.STDDEV
+    @staticmethod
+    def func(*args, **kwargs):
+        return talib.STDDEV(*args, **kwargs)
 
 
 class TwoArgumentSeries(NumericSeries):
diff --git a/setup.py b/setup.py
index 10f66de..edc6f60 100644
--- a/setup.py
+++ b/setup.py
@@ -8,7 +8,10 @@
     setup,
 )
 
-from pip.req import parse_requirements
+try:    # pip >= 10
+    from pip._internal.req import parse_requirements
+except ImportError:
+    from pip.req import parse_requirements
 
 
 with open(join(dirname(__file__), 'funcat/VERSION.txt'), 'rb') as f: