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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 markdown_to_text(self, source):
 """Escape the given source, for a markdown cell"""

        if self.comment and self.comment != "#'":
            source = copy(source)
            comment_magic(source, self.language, self.comment_magics)

        return comment_lines(source, self.comment)