title: cannot start pgadmin4 python app
body: <p>I am missing something, I have downloaded pgadmin4 webapp, and trying to launch it in its environnement:</p>
  
  <pre><code>(pgadmin) denis ~/anaconda3/envs/pgadmin/lib/python3.5/site-packages/pgadmin4 $ pip install flask_babel
  Requirement already satisfied: flask_babel in /home/denis/anaconda3/envs/pgadmin/lib/python3.5/site-packages
  Requirement already satisfied: Jinja2&gt;=2.5 in /home/denis/anaconda3/envs/pgadmin/lib/python3.5/site-packages (from flask_babel)
  Requirement already satisfied: Babel&gt;=2.3 in /home/denis/anaconda3/envs/pgadmin/lib/python3.5/site-packages (from flask_babel)
  Requirement already satisfied: Flask in /home/denis/anaconda3/envs/pgadmin/lib/python3.5/site-packages (from flask_babel)
  Requirement already satisfied: markupsafe in /home/denis/anaconda3/envs/pgadmin/lib/python3.5/site-packages (from Jinja2&gt;=2.5-&gt;flask_babel)
  Requirement already satisfied: pytz&gt;=0a in /home/denis/anaconda3/envs/pgadmin/lib/python3.5/site-packages (from Babel&gt;=2.3-&gt;flask_babel)
  Requirement already satisfied: itsdangerous&gt;=0.21 in /home/denis/.local/lib/python3.5/site-packages (from Flask-&gt;flask_babel)
  Requirement already satisfied: Werkzeug&gt;=0.7 in /home/denis/anaconda3/envs/pgadmin/lib/python3.5/site-packages (from Flask-&gt;flask_babel)
  (pgadmin) denis ~/anaconda3/envs/pgadmin/lib/python3.5/site-packages/pgadmin4 $ sudo python pgAdmin4.py
  Traceback (most recent call last):
    File "pgAdmin4.py", line 34, in &lt;module&gt;
      import config
    File "/home/denis/anaconda3/envs/pgadmin/lib/python3.5/site-packages/pgadmin4/config.py", line 30, in &lt;module&gt;
      from pgadmin.utils import env, IS_PY2, IS_WIN, fs_short_path
    File "/home/denis/anaconda3/envs/pgadmin/lib/python3.5/site-packages/pgadmin4/pgadmin/__init__.py", line 18, in &lt;module&gt;
      from flask_babel import Babel, gettext
  ImportError: No module named flask_babel
  </code></pre>
  
  <p>What can I do more than <code>source activate pgadmin</code> and install all <code>requirements.txt</code>?</p>