Try installing Python manually if Ubuntu is 20.04 to update version

.github/workflows/r.yml

@@ -121,7 +121,7 @@ jobs:
       fail-fast: false
       matrix:
         r: ["4.4"]
-        ubuntu: [22.04]
+        ubuntu: [20.04]
         force-tests: ["true"]
     env:
       R: ${{ matrix.r }}

ci/docker/linux-apt-python-3.dockerfile

@@ -23,6 +23,20 @@ COPY python/requirements-build.txt \
      /arrow/python/
 
 ENV ARROW_PYTHON_VENV /arrow-dev
+
+ARG ubuntu
+ARG python="3.12"
+COPY ci/scripts/install_python.sh /arrow/ci/scripts/
+RUN if [ "${ubuntu}" = "20.04" ]; then \
+        quiet=$([ "${DEBUG}" = "yes" ] || echo "-qq") && \
+        apt update ${quiet} && \
+        apt install -y -V ${quiet} \
+          xz-utils && \
+        apt clean && \
+        rm -rf /var/lib/apt/lists/* && \
+        /arrow/ci/scripts/install_python.sh linux ${python} \
+    ; fi
+
 RUN python3 -m venv ${ARROW_PYTHON_VENV} && \
     . ${ARROW_PYTHON_VENV}/bin/activate && \
     pip install -U pip setuptools wheel && \

ci/scripts/install_python.sh

@@ -68,8 +68,32 @@ if [ $platform = "macOS" ]; then
     python="/Library/Frameworks/Python.framework/Versions/${version}/bin/python${version}"
     pip="${python} -m pip"
 
+    $python -m ensurepip
+    $pip install -U pip setuptools
+elif [ $platform = "Linux" ] ; then
+    echo "Downloading Python installer..."
+
+    if [ "$version" = "3.13" ];
+    then
+        fname="Python-${full_version}rc1.tar.xz"
+    else
+        fname="Python-${full_version}.tar.xz"
+    fi
+    wget "https://www.python.org/ftp/python/${full_version}/${fname}"
+
+    echo "Building and installing Python..."
+    tar -xf ${fname}
+    rm $fname
+    pushd Python-3.*
+    ./configure
+    make install
+    popd
+    python=/usr/local/bin/python3
+    pip="${python} -m pip"
+
     $python -m ensurepip
     $pip install -U pip setuptools
 else
     echo "Unsupported platform: $platform"
+    exit 1
 fi

docker-compose.yml

@@ -984,14 +984,17 @@ services:
     # Parameters:
     #   ARCH: amd64, arm64v8, ...
     #   UBUNTU: 20.04, 22.04
-    image: ${REPO}:${ARCH}-ubuntu-${UBUNTU}-python-3
+    #   PYTHON: 3.9, 3.10, ...
+    image: ${REPO}:${ARCH}-ubuntu-${UBUNTU}-python-${PYTHON}
     build:
       context: .
       dockerfile: ci/docker/linux-apt-python-3.dockerfile
       cache_from:
-        - ${REPO}:${ARCH}-ubuntu-${UBUNTU}-python-3
+        - ${REPO}:${ARCH}-ubuntu-${UBUNTU}-python-${PYTHON}
       args:
         base: ${REPO}:${ARCH}-ubuntu-${UBUNTU}-cpp
+        ubuntu: ${UBUNTU}
+        python: ${PYTHON}
     shm_size: *shm-size
     environment:
       <<: [*common, *ccache]
@@ -1521,6 +1524,8 @@ services:
         tz: ${TZ}
         r_prune_deps: ${R_PRUNE_DEPS}
         r_duckdb_dev: ${R_DUCKDB_DEV:-}
+        ubuntu: ${UBUNTU}
+        python: ${PYTHON}
     shm_size: *shm-size
     environment:
       <<: [*common, *ccache, *sccache]