fix: move import to inside function

setup.py

@@ -1,6 +1,5 @@
 from pathlib import Path
 
-from packaging.version import parse as parse_version
 from setuptools import __version__ as setuptools_version
 from setuptools import find_packages, setup
 
@@ -15,6 +14,8 @@ def has_environment_marker_platform_impl_support():
     it is 18.5, see:
     https://setuptools.readthedocs.io/en/latest/history.html#id235
     """
+    from packaging.version import parse as parse_version
+
     return parse_version(setuptools_version) >= parse_version("18.5")
 
 

tests/requirements.txt

@@ -14,4 +14,3 @@ brotli  # optional for HTTP compress downloader middleware tests
 zstandard; implementation_name != 'pypy'  # optional for HTTP compress downloader middleware tests
 ipython
 pywin32; sys_platform == "win32"
-packaging

tox.ini

@@ -218,6 +218,3 @@ setenv =
     {[pinned]setenv}
 commands =
     pytest --cov=scrapy --cov-report=xml --cov-report= {posargs:tests -k s3}
-
-[build-system]
-build-backend = 'setuptools.build_meta'