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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):
 r"""For new projects, spaces-only are strongly recommended over tabs. Okay: if True:\n return W191: if True:\n\treturn """

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