code: def get_access_bits(self, c1, c2, c3):
          
          byte_6 = ((~c2[3] & 1) << 7) + ((~c2[2] & 1) << 6) + ((~c2[1] & 1) << 5) + ((~c2[0] & 1) << 4) + \
                   ((~c1[3] & 1) << 3) + ((~c1[2] & 1) << 2) + ((~c1[1] & 1) << 1) + (~c1[0] & 1)
          byte_7 = ((c1[3] & 1) << 7) + ((c1[2] & 1) << 6) + ((c1[1] & 1) << 5) + ((c1[0] & 1) << 4) + \
                   ((~c3[3] & 1) << 3) + ((~c3[2] & 1) << 2) + ((~c3[1] & 1) << 1) + (~c3[0] & 1)
          byte_8 = ((c3[3] & 1) << 7) + ((c3[2] & 1) << 6) + ((c3[1] & 1) << 5) + ((c3[0] & 1) << 4) + \
                   ((c2[3] & 1) << 3) + ((c2[2] & 1) << 2) + ((c2[1] & 1) << 1) + (c2[0] & 1)
          return byte_6, byte_7, byte_8
docs: Calculates the access bits for a sector trailer based on their access conditions
          c1, c2, c3, c4 are 4 items tuples containing the values for each block
          returns the 3 bytes for the sector trailer