title: Docker run Error: /bin/sh: 1: python: not found
body: <p>So, im trying to learn docker and tried making a simple image to try it out. The docker build part goes well but when I docker run, I get a problem: </p>
  
  <pre><code>(base) daniellombardi@Daniels-MacBook-Pro MyApp-test % docker run bd
  /bin/sh: 1: python: not found
  </code></pre>
  
  <p>The Dockerfile:</p>
  
  <pre><code>FROM ubuntu
  
  RUN apt-get update &amp;&amp; apt-get install -y python3 python3-pip
  
  RUN pip3 install flask
  
  RUN mkdir /MyApp-test
  
  ADD folder /opt/MyApp-test
  
  EXPOSE 5000
  
  CMD python .main.py
  </code></pre>
  
  <p>and for anyone wondering, this is the code on main.py</p>
  
  <pre><code>from flask import Flask
  
  app = Flask(__name__)
  
  
  @app.route('/')
  def index():
      return 'IT WORKED! I AM RUNNING FROM A DOCKER CONTAINER!!!'
  
  
  if __name__ == '__main__':
      app.run(host="0.0.0.0", port=5000)
  </code></pre>