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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 handle_one_of(schema, field, validator, parent_schema):
 """Adds the validation logic for ``marshmallow.validate.OneOf`` by setting the JSONSchema `enum` property to the allowed choices in the validator. Args: schema (dict):
 The original JSON schema we generated. This is what we want to post-process. field (fields.Field):
 The field that generated the original schema and who this post-processor belongs to. validator (marshmallow.validate.OneOf):
 The validator attached to the passed in field. parent_schema (marshmallow.Schema):
 The Schema instance that the field belongs to. Returns: dict: A, possibly, new JSON Schema that has been post processed and altered. """

    if validator.choices:
        schema['enum'] = list(validator.choices)
        schema['enumNames'] = list(validator.labels)

    return schema