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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 lower_and_check_unique(dict_to_check):
 """ Takes a dictionary and makes all the keys lower case. Also replaces "jobtype" with "job_type" just so that key specifically can be called elsewhere without ambiguity. Finally, ensures that multiple identical keys, that differed only due to different capitalizations, are not present. If there are multiple equivalent keys, an Exception is raised. Args: dict_to_check (dict):
 The dictionary to check and standardize Returns: to_return (dict):
 An identical dictionary but with all keys made lower case and no identical keys present. """

    if dict_to_check == None:
        return None
    else:
        to_return = {}
        for key in dict_to_check:
            new_key = key.lower()
            if new_key == "jobtype":
                new_key = "job_type"
            if new_key in to_return:
                raise Exception(
                    "Multiple instances of key " + new_key + " found!")
            else:
                try:
                    to_return[new_key] = dict_to_check.get(key).lower()
                except AttributeError:
                    to_return[new_key] = dict_to_check.get(key)
        return to_return