fix ci

Author: lucywang000

tox.ini

@@ -25,6 +25,8 @@ commands =
 [testenv:typing]
 basepython = python3
 deps =
+    # mypy would error if pytest (or its sub) not found
+    pytest
     mypy==0.910
 commands =
     mypy --show-error-codes {posargs: w3lib tests}

w3lib/util.py

@@ -6,6 +6,12 @@
 def str_to_unicode(
     text: StrOrBytes, encoding: Optional[str] = None, errors: str = "strict"
 ) -> str:
+    warn(
+        "The w3lib.utils.str_to_unicode function is deprecated and "
+        "will be removed in a future release.",
+        DeprecationWarning,
+        stacklevel=2,
+    )
     if encoding is None:
         encoding = "utf-8"
     if isinstance(text, bytes):
@@ -64,7 +70,7 @@ def to_bytes(
 def to_native_str(
     text: StrOrBytes, encoding: Optional[str] = None, errors: str = "strict"
 ) -> str:
-    """ Return str representation of `text` """
+    """Return str representation of `text`"""
     warn(
         "The w3lib.utils.to_native_str function is deprecated and "
         "will be removed in a future release. Please use "