Code example of how to get the current directory, change directories, and set the output to someplace specific – designed to work on both windows and unix.
# Finds the directory that a program was run from, change the directory
# and creates an output file within a subdirectory. This code is designed
# to run on both mac and windows.
# what is the current working directory? notice the difference when running
# from unix/mac verses windows
# change the current working directory. use forward slash regardless of unix
# or windows
# create a file in a subdirectory from the current working directory
# this method makes the results operating system agnostic
# each entry in the parameters is the next directory level, ending with the
# file name os.path.join inserts the appropriate separators
file_path = os.path.join(wd,"xml","output.xml")
# file is now open as 'f'