add FROM_ARCH

Dockerfile

@@ -1,4 +1,19 @@
-FROM python:3.7-alpine as base
+ARG FROM_ARCH=amd64
+
+FROM alpine as builder
+
+# Download QEMU, see https://github.com/ckulka/docker-multi-arch-example
+ADD https://github.com/balena-io/qemu/releases/download/v3.0.0%2Bresin/qemu-3.0.0+resin-arm.tar.gz .
+RUN tar zxvf qemu-3.0.0+resin-arm.tar.gz --strip-components 1
+ADD https://github.com/balena-io/qemu/releases/download/v3.0.0%2Bresin/qemu-3.0.0+resin-aarch64.tar.gz .
+RUN tar zxvf qemu-3.0.0+resin-aarch64.tar.gz --strip-components 1
+
+FROM $FROM_ARCH/python:3.7-alpine as base
+
+# Add QEMU
+# Add QEMU
+COPY --from=builder qemu-arm-static /usr/bin
+COPY --from=builder qemu-aarch64-static /usr/bin
 
 FROM base as builder