chore: remove ddtrace patch.py files from layer (#763)

chore: remove ddtrace patch.py files from layer

version gate the patch.py file removing

Apply suggestion from @brettlangdon

Co-authored-by: brett.langdon <brett.langdon@datadoghq.com>

Author: brettlangdon

Dockerfile

@@ -62,10 +62,16 @@ RUN rm -rf \
 # https://docs.python.org/3.11/using/cmdline.html#cmdoption-O
 # https://docs.python.org/3/using/cmdline.html#envvar-PYTHONNODEBUGRANGES
 RUN PYTHONNODEBUGRANGES=1 python -OO -m compileall -b ./python/lib/$runtime/site-packages
-# remove all .py files except ddtrace/contrib/*/patch.py which are necessary
-# for ddtrace.patch to discover instrumationation packages.
-RUN find ./python/lib/$runtime/site-packages -name \*.py | grep -v ddtrace/contrib | xargs rm -rf
-RUN find ./python/lib/$runtime/site-packages/ddtrace/contrib -name \*.py | grep -v patch.py | xargs rm -rf
+# remove all .py files
+# DEV: ddtrace>=4.7.0rc4 checks for .pyc files in addition to .py files for instrumentation
+# discovery (DataDog/dd-trace-py#17196), so we can safely remove all .py files.
+# For older versions, we need to keep patch.py files for instrumentation discovery.
+RUN if python -c "from packaging.version import Version; import ddtrace; exit(0 if Version(ddtrace.__version__) >= Version('4.7.0rc3') else 1)"; then \
+        find ./python/lib/$runtime/site-packages -name \*.py | xargs rm -rf; \
+    else \
+        find ./python/lib/$runtime/site-packages -name \*.py | grep -v ddtrace/contrib | xargs rm -rf && \
+        find ./python/lib/$runtime/site-packages/ddtrace/contrib -name \*.py | grep -v patch.py | xargs rm -rf; \
+    fi
 RUN find ./python/lib/$runtime/site-packages -name __pycache__ -type d -exec rm -r {} \+
 
 # When building ddtrace from branch, remove extra source files.  These are