diff --git a/Dockerfile b/Dockerfile
index f60cafc..270927a 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM python:3.10.0
+FROM python:3.11.0
 
 RUN apt-get update && \
     apt-get install -y software-properties-common
diff --git a/src/util/color_reader.py b/src/util/color_reader.py
index f6df576..224e779 100644
--- a/src/util/color_reader.py
+++ b/src/util/color_reader.py
@@ -1,13 +1,13 @@
 import re
 from typing import Tuple
 from colorsys import hls_to_rgb
-from webcolors import HTML4_HEX_TO_NAMES, hex_to_rgb, rgb_to_name, rgb_percent_to_hex, rgb_to_hex, CSS3_NAMES_TO_HEX
+from webcolors import html4_hex_to_names, hex_to_rgb, rgb_to_name, rgb_percent_to_hex, rgb_to_hex, css3_hex_to_names
 
 
 def closest_colour_rgb(requested_color: Tuple[int, ...]) -> str:
     """ Function finds closes colour rgb """
     min_colours = {}
-    for key, name in HTML4_HEX_TO_NAMES.items():
+    for key, name in html4_hex_to_names.items():
         r_c, g_c, b_c = hex_to_rgb(key)
         rd = (r_c - requested_color[0]) ** 2
         gd = (g_c - requested_color[1]) ** 2
@@ -76,7 +76,7 @@ def str2closest_html_color_name(s: str) -> str:
 
         return name
 
-    elif s in HTML4_HEX_TO_NAMES.items():
+    elif s in html4_hex_to_names.items():
         return s
     else:
         return ""
@@ -124,8 +124,8 @@ def str2hex(s: str) -> str:
                 rgb = rgba2rgb(*rgb, alpha)
             return rgb_to_hex(rgb)
 
-    if s.lower() in CSS3_NAMES_TO_HEX:
-        return CSS3_NAMES_TO_HEX[s.lower()]
+    if s.lower() in css3_hex_to_names:
+        return css3_hex_to_names[s.lower()]
 
     return ""