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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 start(cls, callback, provider='gps', min_time=1000, min_distance=0):
 """ Convenience method that checks and requests permission if necessary and if successful calls the callback with a populated `Location` instance on updates. Note you must have the permissions in your manifest or requests will be denied immediately. """

        app = AndroidApplication.instance()
        f = app.create_future()

        def on_success(lm):
            #: When we have finally have permission
            lm.onLocationChanged.connect(callback)

            #: Save a reference to our listener
            #: because we may want to stop updates
            listener = LocationManager.LocationListener(lm)
            lm.listeners.append(listener)

            lm.requestLocationUpdates(provider, min_time, min_distance,
                                      listener)
            app.set_future_result(f, True)

        def on_perm_request_result(allowed):
            #: When our permission request is accepted or decliend.
            if allowed:
                LocationManager.get().then(on_success)
            else:
                #: Access denied
                app.set_future_result(f, False)

        def on_perm_check(allowed):
            if allowed:
                LocationManager.get().then(on_success)
            else:
                LocationManager.request_permission(
                    fine=provider == 'gps').then(on_perm_request_result)

        #: Check permission
        LocationManager.check_permission(
            fine=provider == 'gps').then(on_perm_check)

        return f