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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 error_handler(response, **kwargs):
 """Error Handler to surface 4XX and 5XX errors. Attached as a callback hook on the Request object. Parameters response (requests.Response) The HTTP response from an API request. **kwargs Arbitrary keyword arguments. Raises ClientError (ApiError) Raised if response contains a 4XX status code. ServerError (ApiError) Raised if response contains a 5XX status code. Returns response (requests.Response) The original HTTP response from the API request. """

    try:
        body = response.json()
    except ValueError:
        body = {}
    status_code = response.status_code
    message = body.get('message', '')
    fields = body.get('fields', '')
    error_message = str(status_code) + ': ' + message + ' ' + str(fields)
    if 400 <= status_code <= 499:
        raise ClientError(response, error_message)

    elif 500 <= status_code <= 599:
        raise ServerError(response, error_message)

    return response