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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 iscm_md_update_dict(self, keypath, data):
 """ Update a metadata dictionary entry """

        current = self.metadata
        for k in string.split(keypath, "."):
            if not current.has_key(k):
                current[k] = {}
            current = current[k]
        current.update(data)