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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 survey_loader(sur_dir=SUR_DIR, sur_file=SUR_FILE):
 """Loads up the given survey in the given dir."""

    survey_path = os.path.join(sur_dir, sur_file)
    survey = None
    with open(survey_path) as survey_file:
        survey = Survey(survey_file.read())
    return survey