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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 _build_sliced_filepath(filename, slice_count):
 """ append slice_count to the end of a filename """

    root = os.path.splitext(filename)[0]
    ext = os.path.splitext(filename)[1]
    new_filepath = ''.join((root, str(slice_count), ext))
    return _build_filepath_for_phantomcss(new_filepath)