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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 _line_iter(self, in_handle):
 """Read tab delimited file, handling ISA-Tab special case headers. """

        reader = csv.reader(in_handle, dialect="excel-tab")
        for line in reader:
            if len(line) > 0 and line[0]:
                # check for section headers; all uppercase and a single value
                if line[0].upper() == line[0] and "".join(line[1:]) == "":
                    line = [line[0]]
                yield line