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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 _has(self, key, exact=0):
 """Returns false if key is not found or is ambiguous"""


        if not exact:
            try:
                key = self.getfullkey(key)
                return 1
            except KeyError:
                return 0
        else:
            return key in self.data