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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 force_delete_file(file_path):
        ''' force delete a file '''
        if os.path.isfile(file_path):
            try:
                os.remove(file_path)
                return file_path
            except:           
                return FileSystemUtils.add_unique_postfix(file_path)
        else:
            return file_path