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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 truncate_cwd(full_filename):
 """Remove the cwd from the full filename."""

    if full_filename.startswith(os.getcwd()):
        truncated_filename = full_filename.split(os.getcwd(), 1)[1]
        truncated_filename = truncated_filename.split(os.sep, 1)[1]
    else:
        truncated_filename = full_filename
    return truncated_filename