Add missing 3.9-rc/buster/slim

This was missed in docker-library/python#439 and noticed in docker-library/python#508.

Author: tianon

3.9-rc/buster/slim/Dockerfile

@@ -0,0 +1,142 @@
+#
+# NOTE: THIS DOCKERFILE IS GENERATED VIA "update.sh"
+#
+# PLEASE DO NOT EDIT IT DIRECTLY.
+#
+
+FROM debian:buster-slim
+
+# ensure local python is preferred over distribution python
+ENV PATH /usr/local/bin:$PATH
+
+# http://bugs.python.org/issue19846
+# > At the moment, setting "LANG=C" on a Linux system *fundamentally breaks Python 3*, and that's not OK.
+ENV LANG C.UTF-8
+
+# runtime dependencies
+RUN apt-get update && apt-get install -y --no-install-recommends \
+		ca-certificates \
+		netbase \
+	&& rm -rf /var/lib/apt/lists/*
+
+ENV GPG_KEY E3FF2839C048B25C084DEBE9B26995E310250568
+ENV PYTHON_VERSION 3.9.0b5
+
+RUN set -ex \
+	\
+	&& savedAptMark="$(apt-mark showmanual)" \
+	&& apt-get update && apt-get install -y --no-install-recommends \
+		dpkg-dev \
+		gcc \
+		libbluetooth-dev \
+		libbz2-dev \
+		libc6-dev \
+		libexpat1-dev \
+		libffi-dev \
+		libgdbm-dev \
+		liblzma-dev \
+		libncursesw5-dev \
+		libreadline-dev \
+		libsqlite3-dev \
+		libssl-dev \
+		make \
+		tk-dev \
+		uuid-dev \
+		wget \
+		xz-utils \
+		zlib1g-dev \
+# as of Stretch, "gpg" is no longer included by default
+		$(command -v gpg > /dev/null || echo 'gnupg dirmngr') \
+	\
+	&& wget -O python.tar.xz "https://www.python.org/ftp/python/${PYTHON_VERSION%%[a-z]*}/Python-$PYTHON_VERSION.tar.xz" \
+	&& wget -O python.tar.xz.asc "https://www.python.org/ftp/python/${PYTHON_VERSION%%[a-z]*}/Python-$PYTHON_VERSION.tar.xz.asc" \
+	&& export GNUPGHOME="$(mktemp -d)" \
+	&& gpg --batch --keyserver ha.pool.sks-keyservers.net --recv-keys "$GPG_KEY" \
+	&& gpg --batch --verify python.tar.xz.asc python.tar.xz \
+	&& { command -v gpgconf > /dev/null && gpgconf --kill all || :; } \
+	&& rm -rf "$GNUPGHOME" python.tar.xz.asc \
+	&& mkdir -p /usr/src/python \
+	&& tar -xJC /usr/src/python --strip-components=1 -f python.tar.xz \
+	&& rm python.tar.xz \
+	\
+	&& cd /usr/src/python \
+	&& gnuArch="$(dpkg-architecture --query DEB_BUILD_GNU_TYPE)" \
+	&& ./configure \
+		--build="$gnuArch" \
+		--enable-loadable-sqlite-extensions \
+		--enable-optimizations \
+		--enable-option-checking=fatal \
+		--enable-shared \
+		--with-system-expat \
+		--with-system-ffi \
+		--without-ensurepip \
+	&& make -j "$(nproc)" \
+		LDFLAGS="-Wl,--strip-all" \
+	&& make install \
+	&& rm -rf /usr/src/python \
+	\
+	&& find /usr/local -depth \
+		\( \
+			\( -type d -a \( -name test -o -name tests -o -name idle_test \) \) \
+			-o \( -type f -a \( -name '*.pyc' -o -name '*.pyo' -o -name '*.a' \) \) \
+		\) -exec rm -rf '{}' + \
+	\
+	&& ldconfig \
+	\
+	&& apt-mark auto '.*' > /dev/null \
+	&& apt-mark manual $savedAptMark \
+	&& find /usr/local -type f -executable -not \( -name '*tkinter*' \) -exec ldd '{}' ';' \
+		| awk '/=>/ { print $(NF-1) }' \
+		| sort -u \
+		| xargs -r dpkg-query --search \
+		| cut -d: -f1 \
+		| sort -u \
+		| xargs -r apt-mark manual \
+	&& apt-get purge -y --auto-remove -o APT::AutoRemove::RecommendsImportant=false \
+	&& rm -rf /var/lib/apt/lists/* \
+	\
+	&& python3 --version
+
+# make some useful symlinks that are expected to exist
+RUN cd /usr/local/bin \
+	&& ln -s idle3 idle \
+	&& ln -s pydoc3 pydoc \
+	&& ln -s python3 python \
+	&& ln -s python3-config python-config
+
+# if this is called "PIP_VERSION", pip explodes with "ValueError: invalid truth value '<VERSION>'"
+ENV PYTHON_PIP_VERSION 20.2
+# https://github.com/pypa/get-pip
+ENV PYTHON_GET_PIP_URL https://github.com/pypa/get-pip/raw/cb5b85a8e0c3d13ced611b97816d7490d2f1497e/get-pip.py
+ENV PYTHON_GET_PIP_SHA256 a30ff8a3446c592c6d70403a82483716e7b759e8eecba2c8d3f6ecfb34a8d6d7
+
+RUN set -ex; \
+	\
+	savedAptMark="$(apt-mark showmanual)"; \
+	apt-get update; \
+	apt-get install -y --no-install-recommends wget; \
+	\
+	wget -O get-pip.py "$PYTHON_GET_PIP_URL"; \
+	echo "$PYTHON_GET_PIP_SHA256 *get-pip.py" | sha256sum --check --strict -; \
+	\
+	apt-mark auto '.*' > /dev/null; \
+	[ -z "$savedAptMark" ] || apt-mark manual $savedAptMark; \
+	apt-get purge -y --auto-remove -o APT::AutoRemove::RecommendsImportant=false; \
+	rm -rf /var/lib/apt/lists/*; \
+	\
+	python get-pip.py \
+		--disable-pip-version-check \
+		--no-cache-dir \
+		"pip==$PYTHON_PIP_VERSION" \
+	; \
+	pip --version; \
+	\
+	find /usr/local -depth \
+		\( \
+			\( -type d -a \( -name test -o -name tests -o -name idle_test \) \) \
+			-o \
+			\( -type f -a \( -name '*.pyc' -o -name '*.pyo' \) \) \
+		\) -exec rm -rf '{}' +; \
+	rm -f get-pip.py
+
+CMD ["python3"]