title: Elegant way to take basename of directory in Python?
body: <p>I have several scripts that take as input a directory name, and my program creates files in those directories. Sometimes I want to take the basename of a directory given to the program and use it to make various files in the directory.  For example,</p>
  
  <pre><code># directory name given by user via command-line
  output_dir = "..." # obtained by OptParser, for example
  my_filename = output_dir + '/' + os.path.basename(output_dir) + '.my_program_output'
  # write stuff to my_filename
  </code></pre>
  
  <p>The problem is that if the user gives a directory name with a trailing slash, then os.path.basename will return the empty string, which is not what I want. What is the most elegant way to deal with these slash/trailing slash issues in python? I know I can manually check for the slash at the end of output_dir and remove it if it's there, but there seems like there should be a better way.  Is there?</p>
  
  <p>Also, is it OK to manually add '/' characters?  E.g. output_dir + '/' os.path.basename() or is there a more generic way to build up paths?</p>
  
  <p>Thanks.</p>