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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_pid(options):
 """returns The default location of the pid file for process management"""

    namespace = options['settings'] if options['settings'] else options['wsgi']
    return os.path.join('{}', '{}_{}.pid').format(PID_DIR, options['http_port'], namespace.replace('.', '_'))