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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 datasets(ctx):
 """Read and write GeoJSON from Mapbox-hosted datasets All endpoints require authentication. An access token with appropriate dataset scopes is required, see `mapbox --help`. Note that this API is currently a limited-access beta. """


    access_token = (ctx.obj and ctx.obj.get('access_token')) or None
    service = mapbox.Datasets(access_token=access_token)
    ctx.obj['service'] = service