fix: formatting, pydocs, comments for sep30

nilla.nix

···
           src = pins.nixpkgs;
         };
       };
-      shells.default = {
+      shells.default = config.shells.python;
+      shells.python = {
         # Declare what systems the shell can be used on.
         systems = [ "x86_64-linux" ];
 
···
           mkShell {
             packages = [
               pkgs.python314
+              pkgs.black
             ];
           };
       };

python/assignments/sep30/level1/numberOfBricks.py

···
 
 
 def numberOfBricks(steps: int) -> int:
+    """Calculate the number of bricks in some steps using arithmetic series: S(n) = n(n+1)/2."""
     return ceil((steps * (steps + 1)) / 2)
 
 

python/assignments/sep30/level1/pizzas.py

···
 def howManyPizzas(students: int, slicesPerStudent: int) -> int:
+    """Check how many pizzas are needed given that each pizza has 8 slices."""
     neededSlices = students * slicesPerStudent
     return (neededSlices + 7) // 8
 
 
 def leftoverPizzaSlices(students: int, slicesPerStudent: int) -> int:
+    """Check how many slices of pizza will be leftover given that each pizza has 8 slices."""
     neededSlices = students * slicesPerStudent
     totalSlices = howManyPizzas(students, slicesPerStudent) * 8
     return totalSlices - neededSlices

python/assignments/sep30/level1/pythagoreanTriple.py

···
 def isPythagoreanTriple(a: float, b: float, c: float) -> bool:
+    """
+    Return true if all the following are True:
+    - check that numbers are ascending
+    - check that a^2 + b^2 = c^2
+    - check that a, b, and c are positive
+    """
     return (
         (a < b and b < c) and ((a**2 + b**2) == c**2) and not (a < 0 or b < 0 or c < 0)
     )

python/assignments/sep30/level1/triangleArea.py

···
 
 
 def triangleArea(a: float, b: float, c: float) -> float:
+    """Use herons formula: `sqrt(sp(sp-a)(sp-b)(sp-c))` to calculate the area of a triangle using it's side lengths."""
     semiperimeter = 0.5 * (a + b + c)
     return sqrt(
         semiperimeter * (semiperimeter - a) * (semiperimeter - b) * (semiperimeter - c)

python/assignments/sep30/level2/dotsOverlap.py

···
 
 
 def distance(a: tuple[float, float], b: tuple[float, float]) -> float:
+    """Calculate the distance between two points using the Euclidean distance formula."""
     return sqrt((b[0] - a[0]) ** 2 + (b[1] - a[1]) ** 2)
 
 
 def dotsOverlap(
     x1: float, y1: float, r1: float, x2: float, y2: float, r2: float
 ) -> bool:
+    """Check if two circles overlap."""
     d = distance((x1, y1), (x2, y2))
     return d <= (r1 + r2)
 

python/assignments/sep30/level2/getGreen.py

···
 def fullRGB(rgb: int) -> str:
+    """Left pad 0's to make the string of length 9."""
     return str(rgb).zfill(9)
 
 
 def getGreen(rgb: int) -> int:
+    """Return the green portion of an RGB value."""
     return int(fullRGB(rgb)[3:6])
 
 

python/assignments/sep30/level2/isGray.py

···
 def fullRGB(rgb: int) -> str:
+    """Left pad 0's to make the string of length 9."""
     return str(rgb).zfill(9)
 
 
 def isGray(rgb: int) -> bool:
+    """Return True if the RGB value passed is considered 'gray'."""
     rgbStr = fullRGB(rgb)
     return (rgbStr[0:3] == rgbStr[3:6]) and (rgbStr[3:6] == rgbStr[6:9])
 

python/assignments/sep30/level2/nthFibonacciNumber.py

···
 
 
 def nthFibonacciNumber(n: int) -> float:
+    """Return the nth Fibonacci number."""
     n += 1
     return ((1 + sqrt(5)) ** n - (1 - sqrt(5)) ** n) / (sqrt(5) * 2**n)
 

python/assignments/sep30/level3/numberOfSteps.py

···
 
 
 def numberOfSteps(bricks: int) -> int:
+    """
+    Given a number of bricks return how many steps would be required to use them all given that:
+    S(0) = 0
+    S(n) = S(n-1) + n
+    Formula: `n=(-1+sqrt(1+8*bricks))/2`
+    """
     return ceil((-1 + sqrt(1 + 8 * bricks)) / 2)
 
 

python/assignments/sep30/level3/rectanglesOverlap.py

···
 def rectanglesOverlap(
     ax1: int, ay1: int, aw: float, ah: float, bx1: int, by1: int, bw: float, bh: float
 ) -> bool:
+    """Check if two rectangles overlap."""
     ax2 = ax1 + aw
     ay2 = ay1 + ah
     bx2 = bx1 + bw

python/assignments/sep30/level3/triangeAreaByCoordinates.py

···
 
 
 def distance(a: tuple[float, float], b: tuple[float, float]) -> float:
+    """Calculate the distance between two points using the Euclidean distance formula."""
     return sqrt((b[0] - a[0]) ** 2 + (b[1] - a[1]) ** 2)
 
 
 def triangleArea(a: float, b: float, c: float) -> float:
+    """Calculate the area of a triangle using Heron's formula."""
     semiperimeter = 0.5 * (a + b + c)
     return sqrt(
         semiperimeter * (semiperimeter - a) * (semiperimeter - b) * (semiperimeter - c)
···
 def triangleAreaByCoordinates(
     x1: float, y1: float, x2: float, y2: float, x3: float, y3: float
 ) -> float:
+    """Calculate the area of a triangle given its coordinates."""
     A = distance((x1, y1), (x2, y2))
     B = distance((x2, y2), (x3, y3))
     C = distance((x3, y3), (x1, y1))

python/assignments/sep30/level4/blendColors.py

···
-def halfway(a: int, b: int) -> int:
-    return 0
-
-
 def blendColors(rgb1: int, rgb2: int) -> int:
+    """Blend two colors represented as RGB values."""
     (r1, g1, b1) = [int(str(rgb1).zfill(9)[i : i + 3]) for i in range(0, 9, 3)]
     (r2, g2, b2) = [int(str(rgb2).zfill(9)[i : i + 3]) for i in range(0, 9, 3)]
+    # Calculate the average of each color component
     (r3, g3, b3) = [round((r1 + r2) / 2), round((g1 + g2) / 2), round((b1 + b2) / 2)]
     (final_r, final_g, final_b) = [str(x).zfill(3) for x in (r3, g3, b3)]
     return int(final_r + final_g + final_b)