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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 inject(self, filename, content):
 """ add the injection content to the dictionary """

        # ensure content always has one trailing newline
        content = _unicode(content).rstrip() + "\n"
        if filename not in self.inject_dict:
            self.inject_dict[filename] = ""
        self.inject_dict[filename] += content