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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 get_block_height(height, api_code=None):
 """Get an array of blocks at the specified height. :param int height: block height to look up :param str api_code: Blockchain.info API code (optional) :return: an array of :class:`Block` objects """


    resource = 'block-height/{0}?format=json'.format(height)
    if api_code is not None:
        resource += '&api_code=' + api_code
    response = util.call_api(resource)
    json_response = json.loads(response)
    return [Block(b) for b in json_response['blocks']]