chore: import upstream snapshot with attribution

examples/python3/factorial.py

@@ -0,0 +1,9 @@
+def factorial():
+    f, n = 1, 1
+    while True:            # First iteration:
+        yield f            # yield 1 to start with and then
+        f, n = f * n, n+1  # f will now be 1, and n will be 2, ...
+
+for index, factorial_number in zip(range(51), factorial()):
+     print('{i:3}!= {f:65}'.format(i=index, f=factorial_number))
+

examples/python3/fibonacci.py

@@ -0,0 +1,9 @@
+def fib():
+    a, b = 0, 1
+    while True:            # First iteration:
+        yield a            # yield 0 to start with and then
+        a, b = b, a + b    # a will now be 1, and b will also be 1, (0 + 1)
+
+for index, fibonacci_number in zip(range(100), fib()):
+     print('{i:3}: {f:3}'.format(i=index, f=fibonacci_number))
+

examples/python3/pi.py

@@ -0,0 +1,12 @@
+from decimal import Decimal, getcontext
+getcontext().prec=60
+summation = 0
+for k in range(50):
+	summation = summation + 1/Decimal(16)**k * (
+		Decimal(4)/(8*k+1)
+		- Decimal(2)/(8*k+4)
+		- Decimal(1)/(8*k+5)
+		- Decimal(1)/(8*k+6)
+		)
+	print(summation)
+