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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 funname(file):
 """Return variable names from file names."""

    if isinstance(file, str):
        files = [file]
    else:
        files = file
    bases = [os.path.basename(f) for f in files]
    names = [os.path.splitext(b)[0] for b in bases]
    if isinstance(file, str):
        return names[0]
    else:
        return names