primeiro commit com exercicios de Exercism realizados até esta data

python/grains/grains.py

@@ -0,0 +1,14 @@
+def square(number):
+    grains: int = 1
+    if (number <= 0) or (number > 64):
+        raise ValueError("square must be between 1 and 64")
+    for _ in range(1, number):
+        grains *= 2
+    return grains
+
+
+def total():
+    total_grains: int = 0
+    for square_number in range(1, 65):
+        total_grains += square(square_number)
+    return total_grains