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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 example_write_file_to_disk_if_changed():
 """ Try to remove all comments from a file, and save it if changes were made. """

    my_file = FileAsObj('/tmp/example_file.txt')
    my_file.rm(my_file.egrep('^#'))
    if my_file.changed:
        my_file.save()