diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 027d833..e332fe4 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -15,7 +15,7 @@ jobs:
 
     strategy:
       matrix:
-        python-version: ['3.8', '3.12']
+        python-version: ['3.6', '3.12']
 
     steps:
       - name: Checkout code
diff --git a/miepython/miepython.py b/miepython/miepython.py
index 70952ff..41ec51a 100644
--- a/miepython/miepython.py
+++ b/miepython/miepython.py
@@ -623,7 +623,7 @@ def mie_cdf(m, x, num):
     """
     mu = np.linspace(-1, 1, num)
     intensity_per_mu = i_unpolarized(m, x, mu, norm='4pi') / num
-    cdf = np.cumsum(intensity_per_mu) 
+    cdf = np.cumsum(intensity_per_mu)
     return mu, cdf
 
 
diff --git a/miepython/miepython_nojit.py b/miepython/miepython_nojit.py
index 606441f..7c20403 100644
--- a/miepython/miepython_nojit.py
+++ b/miepython/miepython_nojit.py
@@ -540,7 +540,7 @@ def mie_cdf(m, x, num):
     """
     mu = np.linspace(-1, 1, num)
     intensity_per_mu = i_unpolarized(m, x, mu, norm='4pi') / num
-    cdf = np.cumsum(intensity_per_mu) 
+    cdf = np.cumsum(intensity_per_mu)
     return mu, cdf
 
 
diff --git a/setup.py b/setup.py
index b0ec9d1..936b6e5 100644
--- a/setup.py
+++ b/setup.py
@@ -27,6 +27,7 @@ def get_contents(filename):
 
 setup(
     name=project,
+    python_requires='>=3.6',
     long_description=get_contents('README.rst'),
     long_description_content_type='text/x-rst',
     version=get_init_property('__version__'),