Python Serde EnumField

enumfield.py

from serde import fields, Model
from serde.exceptions import ValidationError

class EnumField(fields.Field):
    """
    A field that can hold the value of an `enum.Enum`.

    Args:
        type: the concrete `Enum` this field can hold.
        **kwargs: keyword arguments for the `Field` constructor.
    """

    def __init__(self, enum=None, **kwargs):
        """
        Create a new `EnumField`.
        """
        if not issubclass(enum, Enum):
            raise TypeError(
                "First argument to EnumField must be a subclass of enum.Enum")

        super().__init__(**kwargs)
        self.enum = enum

    def validate(self, value):
        super().validate(value)
        if not isinstance(value, self.enum):
            raise ValidationError(
                "Expected an instance of {}, but got {} instead".format(
                    self.enum, type(value)),
                value=value
            )

    def serialize(self, value):
        """
        Serialize the given value.
        """
        return value.value

    def deserialize(self, value):
        """
        Deserialize the given value.
        """
        return self.enum[value]