A string in Python is enclosed in either single or double quotes.  Therefore, either one does the trick.  A common practice is to place single words with no characters that can be interpolated in single quotes and multi-word strings that contain interpolated characters in double quotes.  This may be a carry over from Perl where interpolated characters are in double quotes. 

If you do not want to interpolate a string, use a raw string ... r"\n".  With the exception of the last print statement, each of the print statements prints hello on a separate line from how are you?.  They are great for regular expressions.

Finally, triple double quotes """ some message about a function or class ... """ are used for docstrings.

print "hello \n how are you?"
print 'hello \n how are you?'
print r"hello \n how are you?"

Invoking an external command in Python is a two step process:

from subprocess import call
call(["ls","-1"])

There are a lot of articles you will find on the internet that talk about the tenants of having a successful professional career. From soft-skills to job relevant skills, there is an unending list of the do’s and don’ts for establishing a great career. However, a successful career in information technology commands some specific efforts and focus. As a result, it is critical to focus on these 4 key tenants that can help you establish a promising and successful career in Information Technology.

·         Be Multi-lingual– This is the analogy of Steve Job’s famous quote ‘Stay Hungry, Stay Foolish’ as it applies to Information Technology. Gone are the days when you could train yourself on a specific programming language say Java or C++ and code your way to a successful career. The best programmers of today and tomorrow are pushing the limits and becoming experts in one of more languages. Knowing more than one programming language instantly makes you more employable since you can add value to multiple projects that require different languages. If you need proof, IT professionals knowing more than one language can attract a salary premium of £10,000 . Additionally, there is no telling how dynamic technology is and by being open to constantly learning new languages you will position yourself to get technology jobs that did not exist a few years ago

·         Go Beyond the ‘How’, Focus On ‘Why’: A common theme with most information technology professionals is their ability to figure out the HOW or, in other words, applying their technical know-how in achieving the solution to a problem. This is especially true when you are working for a service based IT organization where your key job is to develop a solution for the client’s business problem. Yes, you are and will get paid to be good at the ‘How’ but to advance a career in IT; it will help you immensely to also start focussing on the ‘Why’. This stems from a famous quote by Einsten “If I were given one hour to save the planet, I would spend 59 minutes defining the problem and one minute resolving it”. In essence, spend time in understanding ‘Why’ are your trying to solve the problem before you get down with figuring out the ‘How’ part. The reasons for developing this mindset are two-fold. One, you will instantly distinguish yourself from thousands of other IT peers who are content with the ‘How’ part. Two, there is a good chance that you want to get ahead in your career not only as a programmer but as a system architect or a business solution consultant. This is where the habit of asking the right questions pertaining to why a certain IT solution is requires will help you build the right solution.

·         Focus on the impact and results (Financial impact):This may not apply to IT professionals who are early in their careers but is paramount for senior IT professionals. For the most part, IT departments are required to make sure that the systems and the solutions function as desired and help the business run efficiently. In other words, the key metric for success for most IT professionals is being extremely good at technology, languages and Quality Assurance. However, the times are changing! No longer is the Chief Information Officer (CIO) in charge of making IT decisions. With organizations closely guarding the ROI of their investment in technology, CIOs are increasingly required to be cognizant of the financial benefits of technology so that they can justify the spending on IT. No wonder than that CFOs are increasingly pressurizing CIOs to get their act together

The Zen of Python, by Tim Peters has been adopted by many as a model summary manual of python's philosophy.  Though these statements should be considered more as guideline and not mandatory rules, developers worldwide find the poem to be on a solid guiding ground.

Beautiful is better than ugly.
Explicit is better than implicit.
Simple is better than complex.
Complex is better than complicated.
Flat is better than nested.
Sparse is better than dense.
Readability counts.
Special cases aren't special enough to break the rules.
Although practicality beats purity.
Errors should never pass silently.
Unless explicitly silenced.
In the face of ambiguity, refuse the temptation to guess.
There should be one-- and preferably only one --obvious way to do it.
Although that way may not be obvious at first unless you're Dutch.
Now is better than never.
Although never is often better than *right* now.
If the implementation is hard to explain, it's a bad idea.
If the implementation is easy to explain, it may be a good idea.
Namespaces are one honking great idea -- let's do more of those!