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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 tabs_obsolete(physical_line):
 """ For new projects, spaces-only are strongly recommended over tabs. Most editors have features that make this easy to do. """

    indent = indent_match(physical_line).group(1)
    if indent.count('\t'):
        return indent.index('\t'), "W191 indentation contains tabs"