Update python-musl demo with copy_bom

demos/python/python_musl/python_musl.yaml

@@ -0,0 +1,41 @@
+includes:
+  - base.yaml
+targets:
+  # python
+  - target: /bin
+    copy: 
+      - files:
+          - /root/alpine_python/usr/local/bin/python3.7
+  # dependencies
+  - target: /lib
+    copy:
+      - from: /root/alpine_python/usr/local/lib
+        files: 
+          - libpython3.7m.so.1.0
+          - libpython3.so
+        dirs:
+          - python3.7
+      - from: /root/alpine_python/usr/lib
+        files: 
+          - libblas.so.3
+          - libcblas.so.3
+          - libbz2.so.1
+          - libffi.so.6
+          - libgcc_s.so.1
+          - libgfortran.so.5
+          - liblapack.so.3
+          - liblzma.so.5
+          - libquadmath.so.0
+      - from: /root/alpine_python/lib
+        files:
+          - libz.so.1
+      - files: 
+          - /opt/occlum/toolchains/gcc/x86_64-linux-musl/lib/libstdc++.so.6
+  # below are python code and data
+  - target: /
+    copy:
+      - from: ..
+        dirs:
+          - dataset
+        files: 
+          - demo.py

demos/python/python_musl/run_python_on_occlum.sh

@@ -18,22 +18,8 @@ cd occlum_instance
 
 # 2. Copy files into Occlum Workspace and build
 if [ ! -d "image/lib/python3.7" ];then
-    cp -f $alpine_fs/usr/local/bin/python3.7 image/bin
-    cp -f $alpine_fs/usr/local/lib/libpython3.7m.so.1.0 image/lib
-    cp -f $alpine_fs/usr/local/lib/libpython3.so image/lib
-    cp -rf $alpine_fs/usr/local/lib/python3.7 image/lib
-    cp -f $alpine_fs/usr/lib/libblas.so.3 image/lib
-    cp -f $alpine_fs/usr/lib/libcblas.so.3 image/lib
-    cp -f $alpine_fs/usr/lib/libbz2.so.1 image/lib
-    cp -f $alpine_fs/usr/lib/libffi.so.6 image/lib
-    cp -f $alpine_fs/usr/lib/libgcc_s.so.1 image/lib
-    cp -f $alpine_fs/usr/lib/libgfortran.so.5 image/lib
-    cp -f $alpine_fs/usr/lib/liblapack.so.3 image/lib
-    cp -f $alpine_fs/usr/lib/liblzma.so.5 image/lib
-    cp -f $alpine_fs/usr/lib/libquadmath.so.0 image/lib
-    cp -f $alpine_fs/lib/libz.so.1 image/lib
-    cp -rf ../dataset image
-    cp -f ../demo.py image
+    rm -rf image
+    copy_bom -f ../python_musl.yaml --root image --include-dir /opt/occlum/etc/template
     new_json="$(jq '.resource_limits.user_space_size = "320MB" |
                     .resource_limits.kernel_space_heap_size = "256MB" |
                     .process.default_mmap_size = "256MB"' Occlum.json)" && \