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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 _handle_header(self, sline):
 """ A function for lines with only ONE COLUMN. If line has only one column, then it is either a Section or Subsection name. """

        # All characters UPPER CASE means it is a Section.
        if sline[0].isupper():
            self._cur_section = sline[0]
            self._cur_sub_section = ''
            return 0
        else:
            self._cur_sub_section = sline[0]
            if sline[0] == SUBSECTION_ANALYTE_RESULT:
                # This is Analyte Result Line, next line will be headers of
                # results table
                self._is_header_line = True
                return 0
            elif sline[0] in ('Detail', 'Errors', 'Messages'):
                # It is end of Analyte Result sub-section. Add the last
                # record as a raw result and reset everything.
                self._submit_result()
                return 0