fix: replace strtobool for local function

Author: ZandorLeal

decouple.py

@@ -5,7 +5,7 @@
 from shlex import shlex
 from io import open
 from collections import OrderedDict
-from distutils.util import strtobool
+from util import strtobool
 
 # Useful for very coarse version differentiation.
 PYVERSION = sys.version_info

tests/test_util.py

@@ -0,0 +1,21 @@
+import pytest
+from util import strtobool
+
+
+def test_true_values():
+    true_list = ["y", "yes", "t", "true", "on", "1"]
+    for item in true_list:
+        assert strtobool(item) == 1
+
+
+def test_false_values():
+    false_list = ["n", "no", "f", "false", "off", "0"]
+    for item in false_list:
+        assert strtobool(item) == 0
+
+
+def test_invalid_value_text():
+    invalid_list = ["Invalid_Value_1", "1nv4l1d_V4lu3_2", "Invalid_Value_3"]
+    for value in invalid_list:
+        with pytest.raises(ValueError, match="invalid truth value '%s'".format(value)):
+            strtobool(value)

util.py

@@ -0,0 +1,9 @@
+def strtobool(value):
+    value = value.lower()
+    if value in ["y", "yes", "t", "true", "on", "1"]:
+        result = True
+    elif value in ["n", "no", "f", "false", "off", "0"]:
+        result = False
+    else:
+        raise ValueError("invalid truth value '%s'".format(value))
+    return result