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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 register_drops(self, dropin):
 """Register the `drops` in given `dropin` to a flask app. Args: app (Flask):
 the flask app to be initialized dropin (string):
 path of a python module or object, e.g. dropin.auth This is the only method that a drops loader **must** implment. The default behavior in the base loader is to store all the drops object in the app's extentions dict. For example, the drops with type `models` will be stored in a list which is accessible through:: app.extensions['dropin']['models'] or through DropInManager instance which provide a simple proxy to the dropin extension of `current_app`:: dropin = DropInManager() dropin.models Whereas the BlueprintsLoader overrided this method to actually register the blueprints to the app. """

        drops = self.app.extensions['dropin'].setdefault(self.drops_type, [])
        drops.extend(self.load_drops(dropin))