Export environment variable outside of docker build process

Dockerfile

@@ -16,9 +16,8 @@ COPY .env .env
 # Install python packages
 COPY requirements.txt requirements.txt
 RUN pip install --no-cache-dir -r requirements.txt
-WORKDIR /usr/src/app/ipython/
-RUN export IPYTHONDIR=$(pwd)
+ENV IPYTHONDIR /usr/src/app/startup/
 WORKDIR /usr/src/app/ipython/profile_default/startup/
 COPY python_startup/ ./
-
+WORKDIR /home/