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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 get_entry(self, key, column=None, table=None):
 """Get a specific entry."""

        if table is None:  table  = self.main_table
        if column is None: column = "id"
        if isinstance(key, basestring): key = key.replace("'","''")
        query = 'SELECT * from "%s" where "%s"=="%s" LIMIT 1;'
        query = query % (table, column, key)
        self.own_cursor.execute(query)
        return self.own_cursor.fetchone()