diff --git a/poetry.lock b/poetry.lock
index f0e2dd8..a6645da 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -566,6 +566,23 @@ doc = ["nb2plots (>=0.7)", "nbconvert (<7.9)", "numpydoc (>=1.6)", "pillow (>=9.
 extra = ["lxml (>=4.6)", "pydot (>=1.4.2)", "pygraphviz (>=1.11)", "sympy (>=1.10)"]
 test = ["pytest (>=7.2)", "pytest-cov (>=4.0)"]
 
+[[package]]
+name = "networkx-stubs"
+version = "0.0.1"
+description = "Typing stubs for NetworkX"
+optional = false
+python-versions = "*"
+files = [
+    {file = "networkx-stubs-0.0.1.tar.gz", hash = "sha256:1751cbc87898328f89d79476ec6363174c05f9e48592f0953cc1077188717a21"},
+    {file = "networkx_stubs-0.0.1-py3-none-any.whl", hash = "sha256:ce58dff9b9dcbfdf895d0fce20fa8a73f2e82e581004596b7552086b5bb91366"},
+]
+
+[package.dependencies]
+networkx = "*"
+
+[package.extras]
+dev = ["black", "flake8", "flake8-black", "flake8-pyi", "mypy", "setuptools", "wheel"]
+
 [[package]]
 name = "nodeenv"
 version = "1.8.0"
@@ -1375,4 +1392,4 @@ files = [
 [metadata]
 lock-version = "2.0"
 python-versions = "^3.10"
-content-hash = "b05e052aed9ec92c0edf386f9143271d69f3fc6e4c56a638721a16d7fcb2065b"
+content-hash = "0b582360ca444fe39469eaa4a242c74c516ef5e1cf8d4d69be7623dbbd3d6e6b"
diff --git a/pyproject.toml b/pyproject.toml
index f57e7d4..6ea0d45 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -45,6 +45,7 @@ isort = "^5.13.2"
 ruff = "^0.1.8"
 poethepoet = "^0.24.4"
 ipykernel = "^6.27.1"
+networkx-stubs = "^0.0.1"
 
 [build-system]
 requires = ["poetry-core"]
diff --git a/src/holt59/aoc/2023/day24.py b/src/holt59/aoc/2023/day24.py
index e7e481a..645160f 100644
--- a/src/holt59/aoc/2023/day24.py
+++ b/src/holt59/aoc/2023/day24.py
@@ -1,11 +1,8 @@
 import sys
-from collections import defaultdict
-from dataclasses import dataclass
+
 import numpy as np
-
 from sympy import solve, symbols
 
-
 lines = sys.stdin.read().splitlines()
 
 positions = [
@@ -19,7 +16,7 @@ velocities = [
 low, high = [7, 27] if len(positions) <= 10 else [200000000000000, 400000000000000]
 count = 0
 for i, (p1, v1) in enumerate(zip(positions, velocities)):
-    for p2, v2 in zip(positions[i + 1:], velocities[i + 1:]):
+    for p2, v2 in zip(positions[i + 1 :], velocities[i + 1 :]):
         p, r = p1[:2], v1[:2]
         q, s = p2[:2], v2[:2]
 
@@ -31,7 +28,7 @@ for i, (p1, v1) in enumerate(zip(positions, velocities)):
             continue
         else:
             assert rs != 0
-            t = np.cross((q - p), s) / rs 
+            t = np.cross((q - p), s) / rs
             u = np.cross((q - p), r) / rs
 
             if t >= 0 and u >= 0:
@@ -50,14 +47,16 @@ print(f"answer 1 is {answer_1}")
 #   p3 + t3 * v3 == p0 + t3 * v0
 #      ...
 #   pn + tn * vn == p0 + tn * v0
-# 
+#
 
-# we can solve with only 3 lines since each lines contains 3 
+# we can solve with only 3 lines since each lines contains 3
 # equations (x / y / z), so 3 lines give 9 equations and 9
 # variables: position (3), velocities (3) and times (3).
 n = 3
 
-x, y, z, vx, vy, vz, *ts = symbols('x y z vx vy vz ' + ' '.join(f't{i}' for i in range(n + 1)))
+x, y, z, vx, vy, vz, *ts = symbols(
+    "x y z vx vy vz " + " ".join(f"t{i}" for i in range(n + 1))
+)
 equations = []
 for i, ti in zip(range(n), ts):
     for p, d, pi, di in zip((x, y, z), (vx, vy, vz), positions[i], velocities[i]):
diff --git a/src/holt59/aoc/2023/day25.py b/src/holt59/aoc/2023/day25.py
index d6afdf1..9addbf8 100644
--- a/src/holt59/aoc/2023/day25.py
+++ b/src/holt59/aoc/2023/day25.py
@@ -1,24 +1,20 @@
 import sys
-from collections import defaultdict
-from dataclasses import dataclass
+
 import networkx as nx
 
 components = {
     (p := line.split(": "))[0]: p[1].split() for line in sys.stdin.read().splitlines()
 }
 
-targets = {
-    t for c in components for t in components[c] if t not in components
-}
+targets = {t for c in components for t in components[c] if t not in components}
 
-G = nx.Graph()
-G.add_nodes_from(list(components) + list(targets))
-G.add_edges_from((u, v) for u, vs in components.items() for v in vs)
+graph = nx.Graph()
+graph.add_edges_from((u, v) for u, vs in components.items() for v in vs)
 
-cut = nx.minimum_edge_cut(G) 
-G.remove_edges_from(cut)
+cut = nx.minimum_edge_cut(graph)
+graph.remove_edges_from(cut)
 
-c1, c2 = nx.connected_components(G)
+c1, c2 = nx.connected_components(graph)
 
 # part 1
 answer_1 = len(c1) * len(c2)