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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 explicit_start_marker(self, source):
 """Does the python representation of this cell requires an explicit start of cell marker?"""

        if not self.use_cell_markers:
            return False
        if self.metadata:
            return True
        if self.cell_marker_start:
            start_code_re = re.compile('^' + self.comment + r'\s*' + self.cell_marker_start + r'\s*(.*)$')
            end_code_re = re.compile('^' + self.comment + r'\s*' + self.cell_marker_end + r'\s*$')
            if start_code_re.match(source[0]) or end_code_re.match(source[0]):
                return False

        if all([line.startswith(self.comment) for line in self.source]):
            return True
        if LightScriptCellReader(self.fmt).read(source)[1] < len(source):
            return True

        return False