Run python command in .travis.yml

I want to run a python command in a .travis.yml. Example:
python -c "import numpy as np"
If I put this line directly in .travis.yml, the build parser fails because of the -c in the line. Snippet from .travis.yml:

...
- python -c "import numpy as np"
...

As I understand correctly, all lines in .travis.yml should start with a “-” sign.
How can I run this command, not creating a separate bash file (because then I could not see which line produces which log output)? I tried to avoid the \ with - python \-c "import numpy as np", but it does not help.
Thank you.

Apparently, the current travis build version handles the code I describe above, even without the quoting stuff. Sorry for the false alarm. Hope it will remain the in future.