创建一个Database接口，包含connect()方法和disconnect()方法，用于连接和断开数据库连接。然后创建一个MySQLDatabase类和一个OracleDatabase类，它们都实现了Database接口，并分别实现了连接和断开连接的方法。

好的，以下是实现代码：

from abc import ABC, abstractmethod

class Database(ABC):
    @abstractmethod
    def connect(self):
        pass

    @abstractmethod
    def disconnect(self):
        pass


class MySQLDatabase(Database):
    def __init__(self, host, username, password, database):
        self.host = host
        self.username = username
        self.password = password
        self.database = database

    def connect(self):
        print(f"Connecting to MySQL database {self.database} at {self.host} as {self.username}...")
        # 连接MySQL数据库的代码
        print("Connected to MySQL database.")

    def disconnect(self):
        print(f"Disconnecting from MySQL database {self.database} at {self.host}...")
        # 断开MySQL数据库连接的代码
        print("Disconnected from MySQL database.")


class OracleDatabase(Database):
    def __init__(self, host, username, password, database):
        self.host = host
        self.username = username
        self.password = password
        self.database = database

    def connect(self):
        print(f"Connecting to Oracle database {self.database} at {self.host} as {self.username}...")
        # 连接Oracle数据库的代码
        print("Connected to Oracle database.")

    def disconnect(self):
        print(f"Disconnecting from Oracle database {self.database} at {self.host}...")
        # 断开Oracle数据库连接的代码
        print("Disconnected from Oracle database.")

以上是一个基本的实现，你可以根据自己的需求对其进行扩展和修改。