Checking to see if a file exists is a two step process in Python. Simply import the module shown below and invoke the isfile function:

import os.path
os.path.isfile(fname)

As someone who works in many facets of the music industry, I used to seethe with a mixture of anger and jealousy when I would hear people in more “traditional” goods-based industries argue in favor of music content-based piracy. They made all the classic talking points, like “I wouldn’t spend money on this artist normally, and maybe if I like it I’ll spend money on them when they come to town” (which never happened), or “artists are rich and I’m poor, they don’t need my money” (rarely the case), or the worst, “if it were fairly priced and worth paying for, I’d buy it” (not true).  I always wondered if they’d have the same attitude if 63% of the things acquired by customers in their industries weren’t actually paid for, as was conservatively estimated as the case for the music industry in 2009 (other estimations put the figure of pirated music at 95%). Well, we may soon see the answer to curiosities like that. Though one can say with tentative confidence that music piracy is on the decline thanks to services like Spotify and Rdio, it could be looming on the horizon for the entire global, physical supply chain. Yes, I’m talking about 3d printers.

Before I get into the heart of this article, let me take a moment to make one thing clear: I think these machines are incredible. It’s damn near inspiring to think of even a few of their potentially world-changing applications: affordable, perfectly fit prosthetic limbs for wounded servicemen and women; the ability to create a piece of machinery on the spot instead of having to wait for a spare to arrive in the mail, or en route if your car or ship breaks down in a far away place; a company based out of Austin, TX even made a fully functioning firearm from a 3d printer a few months ago.

If these machines become as consumer-friendly and idiot-proof as possible (like computers), it’s possible that in a matter of decades (maybe less), a majority of U.S. households will have their own 3d printer. There’s also the possibility they could take the tech-hobbyist path, one that is much less appealing to the masses. Dale Dougherty of Makezine.com estimates there are currently around 100,000 “personal” 3d printers, or those not owned for business or educational purposes. I don’t think they’ll ever be as ubiquitous as computers, but there are plenty of mechanically inclined, crafty hobbyists out there who would love to play around with a 3d printer if it was affordable enough.

That being said, is there reason to worry about the economic implications of consumers making what they want, essentially for free, instead of paying someone else to produce it? Or will the printers instead be used for unique items more so than replicating and ripping off other companies’ merchandise in mass amounts? The number of people working in industries that would be affected by a development like this is far greater than the number of people who work in content-based industries, so any downturn would probably have a much larger economic implications. Certainly, those times are a ways off, but a little foresightedness never hurt anyone!

I suspect that many of you are familiar with the term "hard coding a value" whereby the age of an individual or their location is written into the condition (or action) of a business rule (in this case) as shown below:

if customer.age > 21 and customer.city == 'denver'

then ...

Such coding practices are perfectly expectable provided that the conditional values, age and city, never change. They become entirely unacceptable if a need for different values could be anticipated. A classic example of where this practice occurred that caused considerable heartache in the IT industry was the Y2K issue where dates were updated using only the last 2 digits of a four digit number because the first 2 digits were hard-coded to 19 i.e. 1998, 1999. All was well provided that the date did not advance to a time beyond the 1900’s since no one could be certain of what would happen when the millennia arrived (2000). A considerably amount of work (albeit boring) and money, approximately $200 billion, went into revising systems by way of software rewrites and computer chip replacements in order to thwart any detrimental outcomes. It is obvious how a simple change or an assumption can have sweeping consequences.

You may wonder what Y2K has to do with Business Rule Management Systems (BRMS). Well, what if we considered rules themselves to be hard-coded. If we were to write 100s of rules in Java, .NET or whatever language that only worked for a given scenario or assumption, would that not constitute hard-coded logic? By hard-coded, we obviously mean compiled. For example, if a credit card company has a variety of bonus campaigns, each with their own unique list of rules that may change within a week’s time, what would be the most effective way of writing software to deal with these responsibilities?

If you are a software developer looking for a slight change, then you have several options available. The process of software development requires multiple types of resources. A software developer performs the construction and delivery of software programs. An experienced software developer gains business knowledge, analytical skills, team management skills and communication skills. All of these skills can be used to divert your development career into a related and slightly varied role in software development.

Production Support Engineer
A developer can easily switch to the role of a Production Support Engineer. This role entails working with customers and technical teams to report, track and resolve production issues. For some, this might be an exciting opportunity to see the software application from a user’s point of view.

Engineering Manager
If you have experience in leading a team of developers, you could take the role of an Engineering Manager. This role requires managing a bigger team of developers. The Engineering Manager is also responsible for ensuring the delivery of software products and meeting the deadlines set by Product Management. You will get the opportunity to develop software, if you are inclined to do so. However, you will also take new responsibilities such as performance management, infrastructure management and vendor management.

Partner Engineer
This role requires some amount development as well as coordination with partners such as vendors and customers. The job of a Partner Engineer is to act as a middleman to help the integration of services with partners via application programming interfaces (APIs). For example, companies such as Twitter and Facebook employ Partner Engineers to integrate their services with customer websites.

Systems Analyst
Many companies offer developers with an opportunity to switch to Analyst roles. This role involves analyzing system requirements by working with business and technical teams. Many Systems Analysts also work on reviewing, developing and testing application code. This role is suitable for developers with strong analytical skills.

QA Automation Engineer
This role is responsible for automating test cases with the help of tools such as Java, Ruby and Selenium. This role is ideal for people with prior development experience. QA Automation Engineers work with developers and product managers to define test cases, and to automate and run the test cases. In this role, you will get the opportunity to work on back-end as well as front-end automation tasks. You will remain in touch with programming languages as well as database technologies.

Database Analyst
Most people gain significant amount of knowledge on databases while working as a software developer. This will help you to switch your role into a Database Analyst. A Database Analyst analyzes database issues, reviews performance problems, writes database scripts and runs queries. This role also provides a path to become a Database Administrator, if you are interested.

Deployment Engineer
This role is responsible for deploying the code developed by software engineers. You may not be developing application programs in this role. However, you will be responsible for code deployments, pushing the code into test and production environments.

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