def get_upload_location(instance, filename):
    """
    This method provides a filename to store an uploaded image.
    Inputs:
    instance: instance of an Observation class
    filename: string

    returns:
    string:
    """
    psr = instance.pulsar.jname
    beam = instance.beam
    utc = instance.utc.utc_ts.strftime("%Y-%m-%d-%H:%M:%S")
    return f"{psr}/{utc}/{beam}/{filename}"