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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 main():
 """ Take out dos problem characters from any file """

    filename = pmag.get_named_arg('-f')
    if not filename:
        return
    with open(filename, 'rb+') as f:
        content = f.read()
        f.seek(0)
        f.write(content.replace(b'\r', b''))
        f.truncate()