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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 build_request_body(type, id, attributes=None, relationships=None):
 """Build a request body object. A body JSON object is used for any of the ``update`` or ``create`` methods on :class:`Resource` subclasses. In normal library use you should not have to use this function directly. Args: type(string):
 The resource type for the attribute id(uuid):
 The id of the object to update. This may be ``None`` Keyword Args: attributes(dict):
 A JSON dictionary of the attributes to set relationships(dict) A JSON dictionary of relationships to set Returns: A valid attribute dictionary. Often used in the ``update`` or ``create`` :class:`Resource`` methods. """

    result = {
        "data": {
            "type": type
        }
    }
    data = result['data']
    if attributes is not None:
        data['attributes'] = attributes
    if relationships is not None:
        data['relationships'] = relationships
    if id is not None:
        data['id'] = id
    return result