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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 retrieve(self, block_height, headers=None):
 """Retrieves the block with the given ``block_height``. Args: block_height (str):
 height of the block to retrieve. headers (dict):
 Optional headers to pass to the request. Returns: dict: The block with the given ``block_height``. """

        path = self.path + block_height
        return self.transport.forward_request(
            method='GET', path=path, headers=None)