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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 ExportMigrations():
 """Exports counts of unapplied migrations. This is meant to be called during app startup, ideally by django_prometheus.apps.AppConfig. """


    # Import MigrationExecutor lazily. MigrationExecutor checks at
    # import time that the apps are ready, and they are not when
    # django_prometheus is imported. ExportMigrations() should be
    # called in AppConfig.ready(), which signals that all apps are
    # ready.
    from django.db.migrations.executor import MigrationExecutor

    if 'default' in connections and (
            type(connections['default']) == DatabaseWrapper):
        # This is the case where DATABASES = {} in the configuration,
        # i.e. the user is not using any databases. Django "helpfully"
        # adds a dummy database and then throws when you try to
        # actually use it. So we don't do anything, because trying to
        # export stats would crash the app on startup.
        return
    for alias in connections.databases:
        executor = MigrationExecutor(connections[alias])
        ExportMigrationsForDatabase(alias, executor)