diff --git a/pyproject.toml b/pyproject.toml
index fbca3dc..9ce4256 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "fasttrackpy"
-version = "0.4.1"
+version = "0.4.2"
 description = "A python implementation of FastTrack"
 authors = [
     "JoFrhwld <JoFrhwld@gmail.com>",
@@ -22,7 +22,7 @@ python = ">=3.10,<3.12"
 praat-parselmouth = "^0.4.3"
 scipy = {version = "^1.11.3", python = ">=3.10,<3.12"}
 numpy = {version = "^1.26.1", python = ">=3.10,<3.12"}
-polars = "^0.19.16"
+polars = "^0.20.18"
 pytest-cov = "^4.1.0"
 pytest = "^7.4.3"
 python-magic = {version = "^0.4.27", markers = "sys_platform != 'win32'"}
diff --git a/src/fasttrackpy/processors/outputs.py b/src/fasttrackpy/processors/outputs.py
index 6c6b5b8..0270256 100644
--- a/src/fasttrackpy/processors/outputs.py
+++ b/src/fasttrackpy/processors/outputs.py
@@ -247,7 +247,7 @@ def spectrogram(
         .melt(id_vars = "time")\
         .with_columns(
             pl.col("variable")\
-            .replace(mapping=ptolmap)\
+            .replace(ptolmap)\
             .alias("color")
             )
 
@@ -348,7 +348,7 @@ def candidate_spectrograms(
                 .melt(id_vars = "time")\
                 .with_columns(
                     pl.col("variable")\
-                    .replace(mapping=ptolmap)\
+                    .replace(ptolmap)\
                     .alias("color")
                 )