bazarr/libs/apprise/utils/singleton.py

# -*- coding: utf-8 -*-
# BSD 2-Clause License
#
# Apprise - Push Notification Library.
# Copyright (c) 2025, Chris Caron <lead2gold@gmail.com>
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
# 1. Redistributions of source code must retain the above copyright notice,
#    this list of conditions and the following disclaimer.
#
# 2. Redistributions in binary form must reproduce the above copyright notice,
#    this list of conditions and the following disclaimer in the documentation
#    and/or other materials provided with the distribution.
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# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
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class Singleton(type):
    """
    Our Singleton MetaClass
    """
    _instances = {}

    def __call__(cls, *args, **kwargs):
        """
        instantiate our singleton meta entry
        """
        if cls not in cls._instances:
            # we have not every built an instance before.  Build one now.
            cls._instances[cls] = super().__call__(*args, **kwargs)
        return cls._instances[cls]