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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 _docstring_key(self, line):
 """Returns the key to use for the docblock immediately preceding the specified line."""

        decormatch = self.docparser.RE_DECOR.match(line)
        if decormatch is not None:
            key = "{}.{}".format(self.docelement.name, decormatch.group("name"))
        else:
            key = self.element.name

        return key