By seven

main.py

@@ -22,6 +22,13 @@ def divide_by_six(num): # Same rules as dividing by three, and ensure original n
     num_sum = _sum_digits(num)
     return num_sum % 3 == 0 and divide_by_two(num)
 
+def divide_by_seven(num): # Multiply last digit by five then add unused digits to result, dividing the result by seven.
+    if (num <= 100): return num % 7 == 0
+    num_as_string = f"{num}"
+    ones_place = _get_last_digit(num) * 5
+    num_to_check = int(f"{num_as_string[:-1]}{ones_place}")
+    return num_to_check % 7 == 0
+
 def divide_by_eight(num): # Same rules as dividing by four, but for last three digits
     if (num <= 100): return num % 8 == 0
     hundreds_place = _get_last_digit(num, 3) * 100

tests/seven_test.py

@@ -0,0 +1,22 @@
+from main import divide_by_seven
+import unittest
+
+class TestDivideBySeven(unittest.TestCase):
+    def test_by_1(self):
+        self.assertFalse(divide_by_seven(1))
+    def test_by_2(self):
+        self.assertFalse(divide_by_seven(2))
+    def test_by_3(self):
+        self.assertFalse(divide_by_seven(3))
+    def test_by_7(self):
+        self.assertTrue(divide_by_seven(7))
+    def test_by_14(self):
+        self.assertTrue(divide_by_seven(14))
+    def test_by_700(self):
+        self.assertTrue(divide_by_seven(700))
+    def test_by_701(self):
+        self.assertFalse(divide_by_seven(701))
+    def test_by_7000(self):
+        self.assertTrue(divide_by_seven(7000))
+    def test_by_362880(self):
+        self.assertTrue(divide_by_seven(362880))