code: def from_p1363(cls, data):
          
  
          r = int_from_bytes(data[0:len(data) // 2])
          s = int_from_bytes(data[len(data) // 2:])
          return cls({'r': r, 's': s})
docs: Reads a signature from a byte string encoding accordint to IEEE P1363,
          which is used by Microsoft's BCryptSignHash() function.
  
          :param data:
              A byte string from BCryptSignHash()
  
          :return:
              A DSASignature object