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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 check_argument_type(long_form, specification_dict):
 """ Ensures that long_form is a pandas dataframe and that specification_dict is an OrderedDict, raising a ValueError otherwise. Parameters long_form : pandas dataframe. Contains one row for each available alternative, for each observation. specification_dict : OrderedDict. Keys are a proper subset of the columns in `long_form_df`. Values are either a list or a single string, `"all_diff"` or `"all_same"`. If a list, the elements should be: - single objects that are within the alternative ID column of `long_form_df` - lists of objects that are within the alternative ID column of `long_form_df`. For each single object in the list, a unique column will be created (i.e. there will be a unique coefficient for that variable in the corresponding utility equation of the corresponding alternative). For lists within the `specification_dict` values, a single column will be created for all the alternatives within iterable (i.e. there will be one common coefficient for the variables in the iterable). Returns ------- None. """

    if not isinstance(long_form, pd.DataFrame):
        msg = "long_form should be a pandas dataframe. It is a {}"
        raise TypeError(msg.format(type(long_form)))

    ensure_object_is_ordered_dict(specification_dict, "specification_dict")

    return None