update download stuff

Dockerfile.cpu

@@ -1,12 +1,8 @@
 FROM tensorflow/tensorflow:1.12.0-py3
 
 ENV LANG=C.UTF-8
-RUN mkdir /gpt-2 
+RUN mkdir /gpt-2
 WORKDIR /gpt-2
-COPY requirements.txt download_model.sh /gpt-2/
-RUN apt-get update && \
-    apt-get install -y curl && \
-    sh download_model.sh 117M
-RUN pip3 install -r requirements.txt
-
 ADD . /gpt-2
+RUN pip3 install -r requirements.txt
+RUN python3 download_model.py 117M