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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 _create_table(self, packet_defn):
        ''' Creates a database table for the given PacketDefinition

        Arguments
            packet_defn
                The :class:`ait.core.tlm.PacketDefinition` instance for which a table entry
                should be made.
        '''
        cols = ('%s %s' % (defn.name, self._getTypename(defn)) for defn in packet_defn.fields)
        sql  = 'CREATE TABLE IF NOT EXISTS %s (%s)' % (packet_defn.name, ', '.join(cols))

        self._conn.execute(sql)
        self._conn.commit()