Better Dockerfile structure

Dockerfile

@@ -8,7 +8,7 @@ ARG UID="1000"
 ARG GID="1000"
 
 
-ENV LANG=C.UTF-8
+ENV LANG="C.UTF-8"
 
 
 RUN apt-get update \
@@ -27,24 +27,22 @@ USER generic
 WORKDIR /home/generic
 
 
-ENV PYTHON2_VENV_PATH="/home/generic/.python2/venvs/venv"
-RUN python2 -m virtualenv "${PYTHON2_VENV_PATH}"
-ENV PYTHON3_VENV_PATH="/home/generic/.python3/venvs/venv"
-RUN python3 -m venv "${PYTHON3_VENV_PATH}"
+ENV PYTHON2_VENV_PATH="/home/generic/python2_venv"
+ENV PYTHON3_VENV_PATH="/home/generic/python3_venv"
+RUN python2 -m virtualenv "${PYTHON2_VENV_PATH}" \
+ && python3 -m venv "${PYTHON3_VENV_PATH}"
 ENV PATH="${PYTHON3_VENV_PATH}/bin:${PYTHON2_VENV_PATH}/bin:${PATH}"
 
 
+COPY --chown=generic:generic packages packages
+COPY --chown=generic:generic requirements.txt .
 ENV PYFLOW_VERSION="1.1.20"
 RUN wget --output-document - --quiet "https://github.com/Illumina/pyflow/releases/download/v${PYFLOW_VERSION}/pyflow-${PYFLOW_VERSION}.tar.gz" | tar -xzf - \
  && cd "pyflow-${PYFLOW_VERSION}" \
  && python2 setup.py build install \
  && cd - > /dev/null \
- && rm -r "pyflow-${PYFLOW_VERSION}"
-
-
-COPY --chown=generic:generic packages packages
-COPY --chown=generic:generic requirements.txt requirements.txt
-RUN python3 -m pip install --upgrade pip \
+ && rm -r "pyflow-${PYFLOW_VERSION}" \
+ && python3 -m pip install --upgrade pip \
  && python3 -m pip install wheel \
  && python3 -m pip install -r requirements.txt \
  && rm -r packages requirements.txt