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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 query_file_location(question, default_address):
 """ This function asks for a location file address from the command terminal it checks if the file exists before proceeding with the code "question" is a string that is presented to the user. "default_address" is the presumed file location. """


    while True:
        if default_address == None:
            prompt = '{}:'.format(question, default_address)
        else:
            prompt = '{} [{}]'.format(question, default_address)

        sys.stdout.write(prompt)
        input_address = raw_input()
        if default_address is not None and input_address == '':
            input_address = default_address
        if os.path.isfile(input_address):
            return input_address
        else:
            print 'sorry no file was found at that location\n'