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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 from_codes(cls, codes, categories=None, ordered=None, dtype=None):
 """ Make a Categorical type from codes and categories or dtype. This constructor is useful if you already have codes and categories/dtype and so do not need the (computation intensive) factorization step, which is usually done on the constructor. If your data does not follow this convention, please use the normal constructor. Parameters codes : array-like, integers An integer array, where each integer points to a category in categories or dtype.categories, or else is -1 for NaN. categories : index-like, optional The categories for the categorical. Items need to be unique. If the categories are not given here, then they must be provided in `dtype`. ordered : bool, optional Whether or not this categorical is treated as an ordered categorical. If not given here or in `dtype`, the resulting categorical will be unordered. dtype : CategoricalDtype or the string "category", optional If :class:`CategoricalDtype`, cannot be used together with `categories` or `ordered`. .. versionadded:: 0.24.0 When `dtype` is provided, neither `categories` nor `ordered` should be provided. Examples -------- [a, b, a, b] Categories (2, object):
 [a < b] """

        dtype = CategoricalDtype._from_values_or_dtype(categories=categories,
                                                       ordered=ordered,
                                                       dtype=dtype)
        if dtype.categories is None:
            msg = ("The categories must be provided in 'categories' or "
                   "'dtype'. Both were None.")
            raise ValueError(msg)

        codes = np.asarray(codes)  # #21767
        if not is_integer_dtype(codes):
            msg = "codes need to be array-like integers"
            if is_float_dtype(codes):
                icodes = codes.astype('i8')
                if (icodes == codes).all():
                    msg = None
                    codes = icodes
                    warn(("float codes will be disallowed in the future and "
                          "raise a ValueError"), FutureWarning, stacklevel=2)
            if msg:
                raise ValueError(msg)

        if len(codes) and (
                codes.max() >= len(dtype.categories) or codes.min() < -1):
            raise ValueError("codes need to be between -1 and "
                             "len(categories)-1")

        return cls(codes, dtype=dtype, fastpath=True)