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a) To authenticate the legitimacy of the response, the last element of the XML serves as a signature. It is a HMAC-MD5 hash based on the values of all XML elements and a key defined at the PagBrasil Dashboard, menu Account > Settings. The HMAC-MD5 source string is the concatenation of all the elements that are present in the XML and its total length. The XML examples below describe how the signature is computed.
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