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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 _warn_dupkey(self, k):
 """ Really odd function - used to help ensure we actually warn for duplicate keys. """

        if self._privflags & PYCBC_CONN_F_WARNEXPLICIT:
            warnings.warn_explicit(
                'Found duplicate keys! {0}'.format(k), RuntimeWarning,
                __file__, -1, module='couchbase_ffi.bucket', registry={})
        else:
            warnings.warn('Found duplicate keys!', RuntimeWarning)