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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_subfolder(txt):
 """ extracts a displayable subfolder name from full filename """

    root_folder = os.sep + 'aikif' + os.sep
    ndx = txt.find(root_folder, 1)
    return txt[ndx:].replace('__init__.py', '')