remove printing (#455)

server/cli/launch.py

@@ -1,6 +1,7 @@
 import sys
 import click
 import logging
+from os import devnull
 from os.path import splitext, basename
 import webbrowser
 
@@ -112,4 +113,8 @@ def launch(data, layout, diffexp, title, verbose, debug, obs_names, var_names,
 
     click.echo("[cellxgene] Type CTRL-C at any time to exit.")
 
+    if not verbose:
+        f = open(devnull, 'w')
+        sys.stdout = f
+
     app.run(host=host, debug=debug, port=port, threaded=True)