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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 copy(copy_entry: FILE_COPY_ENTRY):
 """ Copies the specified file from its source location to its destination location. """

    source_path = environ.paths.clean(copy_entry.source)
    output_path = environ.paths.clean(copy_entry.destination)
    copier = shutil.copy2 if os.path.isfile(source_path) else shutil.copytree
    make_output_directory(output_path)

    for i in range(3):
        try:
            copier(source_path, output_path)
            return
        except Exception:
            time.sleep(0.5)

    raise IOError('Unable to copy "{source}" to "{destination}"'.format(
        source=source_path,
        destination=output_path
    ))