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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 set_sdk_enabled(cls, value):
 """ Modifies the enabled flag if the "AWS_XRAY_SDK_ENABLED" environment variable is not set, otherwise, set the enabled flag to be equal to the environment variable. If the env variable is an invalid string boolean, it will default to true. :param bool value: Flag to set whether the SDK is enabled or disabled. Environment variables AWS_XRAY_SDK_ENABLED overrides argument value. """

        # Environment Variables take precedence over hardcoded configurations.
        if cls.XRAY_ENABLED_KEY in os.environ:
            cls.__SDK_ENABLED = str(os.getenv(cls.XRAY_ENABLED_KEY, 'true')).lower() != 'false'
        else:
            if type(value) == bool:
                cls.__SDK_ENABLED = value
            else:
                cls.__SDK_ENABLED = True
                log.warning("Invalid parameter type passed into set_sdk_enabled(). Defaulting to True...")