diff --git a/.github/workflows/ci_test.yml b/.github/workflows/ci_test.yml
index 32fcf544..58369ab2 100644
--- a/.github/workflows/ci_test.yml
+++ b/.github/workflows/ci_test.yml
@@ -46,8 +46,6 @@ jobs:
           pip install opencv-python
           pip install pycocotools>=2.0.2
           pip install onnxruntime
-          # requirements for ultralytics/yolov5
-          pip install pandas seaborn thop
       - name: Lint with flake8
         run: |
           # stop the build if there are Python syntax errors or undefined names
diff --git a/requirements.txt b/requirements.txt
index b2010605..af9f6bd7 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -31,3 +31,4 @@ torchmetrics
 # extras --------------------------------------
 # pycocotools on PyPI needs python3.7 as minimal
 # pycocotools>=2.0.2  # corresponds to https://github.com/ppwwyyxx/cocoapi
+thop  # FLOPs computation
diff --git a/yolort/v5/utils/plots.py b/yolort/v5/utils/plots.py
index 7f0924d4..c5d8a4d2 100644
--- a/yolort/v5/utils/plots.py
+++ b/yolort/v5/utils/plots.py
@@ -12,7 +12,6 @@
 import matplotlib.pyplot as plt
 import numpy as np
 import pandas as pd
-import seaborn as sn
 import torch
 from PIL import Image, ImageDraw, ImageFont
 
@@ -361,7 +360,12 @@ def plot_study_txt(path="", x=None):
 
 
 def plot_labels(labels, names=(), save_dir=Path("")):
-    # plot dataset labels
+    """
+    Plot dataset labels
+    """
+
+    import seaborn as sn
+
     print("Plotting labels... ")
     c, b = labels[:, 0], labels[:, 1:].transpose()  # classes, boxes
     nc = int(c.max() + 1)  # number of classes