diff --git a/participants/scipy_007/doc/README.md b/participants/scipy_007/doc/README.md
index a1542d9..79fbcea 100644
--- a/participants/scipy_007/doc/README.md
+++ b/participants/scipy_007/doc/README.md
@@ -1,11 +1,11 @@
-Ok so I guess you are reading this cuz you wanna use my code. There are some
-functions that do stuf and thats:
+Ok, so I guess you are reading this cuz you wanna use my code. There are some
+functions that do stuff and that's:
 
     >>> from simple_functions import factorial
     >>> factorial(10)
     9
 
-and this other part does something.  I forget why that I did it:
+and this other part does something.  I forget why I did it:
 
     >>> fibonnaccci(100)
     [0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89]
diff --git a/participants/scipy_007/pr_tutorial/simple_functions.py b/participants/scipy_007/pr_tutorial/simple_functions.py
index c3dcf8f..43f23db 100644
--- a/participants/scipy_007/pr_tutorial/simple_functions.py
+++ b/participants/scipy_007/pr_tutorial/simple_functions.py
@@ -10,3 +10,10 @@ def factorial(value):
         return 1
     else:
         return value * factorial(value - 1)
+
+def isPrime(n):
+    for i in range(2,int(n**0.5)+1):
+        if n%i==0:
+            return False
+        
+    return True