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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 normalize_species_name(name):
 """ If species name was "Homo sapiens" then replace spaces with underscores and return "homo_sapiens". Also replace common names like "human" with "homo_sapiens". """

    lower_name = name.lower().strip()

    # if given a common name such as "human", look up its latin equivalent
    if lower_name in Species._common_names_to_species:
        return Species._common_names_to_species[lower_name].latin_name

    return lower_name.replace(" ", "_")