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"""

Pattern name - SingleTon

Pattern type - Creational Design Pattern

"""

# Solution - 4

class SingletonMeta(type):

__instances = {}

def __call__(cls, *args, **kwargs):

if cls not in cls.__instances:

cls.__instances[cls] = super().__call__(*args, **kwargs)

print(cls.__instances)

return cls.__instances[cls]

class DBConnector(metaclass=SingletonMeta):

def __init__(self):

self.status = "Not Connected"

def disconnect(self):

self.status = "Disconnected"

def connect(self):

self.status = "Connected"

client1 = DBConnector()

print("Client 1 ", client1)

print(client1.status)

client2 = DBConnector()

print("Client 2 ", client2)

client2.connect()

print(client1.status)

client1.disconnect()

print(client2.status)