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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 _chk_sections(sections):
 """Check format of user-provided 'sections' variable"""

        if sections:
            assert len(sections[0]) == 2, \
                "SECTIONS DATA MUST BE A 2-D LIST. FOUND: {S}".format(S=sections)
            for _, hdrgos in sections:
                chk_goids(hdrgos, "HdrgosSections::_chk_sections()")