Add polars as dev dependency, to avoid import-errors in examples

Signed-off-by: Sahas Subramanian <[email protected]>

Author: shsms

pyproject.toml

@@ -58,6 +58,7 @@ docs-lint = [
 ]
 format = ["black == 23.3.0", "isort == 5.12.0"]
 nox = ["nox == 2023.4.22", "toml == 0.10.2"]
+examples = [ "polars == 0.18.0" ]
 pytest = [
   "pytest == 7.3.1",
   "pytest-cov == 4.1.0",
@@ -68,6 +69,7 @@ pytest = [
   # For checking docstring code examples
   "sybil == 5.0.2",
   "pylint == 2.17.4",
+  "frequenz-sdk[examples]",
 ]
 mypy = [
   "mypy == 1.3.0",

src/frequenz/sdk/timeseries/_moving_window.py

@@ -81,7 +81,6 @@ class MovingWindow:
     Example: Create a polars data frame from a `MovingWindow`
 
         ```python
-        # pylint: disable=import-error
         import polars as pl
         from datetime import datetime, timedelta, timezone