Pythagoras (#1243)

* add pythagoras.py

* function distance

* run as script

* Update pythagoras.py

maths/pythagoras.py

@@ -0,0 +1,33 @@
+"""Uses Pythagoras theorem to calculate the distance between two points in space."""
+
+import math
+
+
+class Point:
+    def __init__(self, x, y, z):
+        self.x = x
+        self.y = y
+        self.z = z
+
+    def __repr__(self) -> str:
+        return f"Point({self.x}, {self.y}, {self.z})"
+
+
+def distance(a: Point, b: Point) -> float:
+    return math.sqrt(abs(((b.x - a.x) ** 2 + (b.y - a.y) ** 2 + (b.z - a.z) ** 2)))
+
+
+def test_distance() -> None:
+    """
+    >>> point1 = Point(2, -1, 7)
+    >>> point2 = Point(1, -3, 5)
+    >>> print(f"Distance from {point1} to {point2} is {distance(point1, point2)}")
+    Distance from Point(2, -1, 7) to Point(1, -3, 5) is 3.0
+    """
+    pass
+
+
+if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod()