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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_expiration(self, headers: dict) -> int: """Gets the expiration time of the data from the response headers. Args: headers: dictionary of headers from ESI Returns: value of seconds from now the data expires """

        expiration_str = headers.get('expires')
        if not expiration_str:
            return 0
        expiration = datetime.strptime(expiration_str, '%a, %d %b %Y %H:%M:%S %Z')
        delta = (expiration - datetime.utcnow()).total_seconds()
        return math.ceil(abs(delta))