code: def from_mat_file(cls, matfilename):
          
          M = scipy.io.loadmat(matfilename)
          instance = cls()
          instance.gyro_data = M['gyro']
          instance.timestamps = M['timestamps']
          return instance
docs: Load gyro data from .mat file
          
          The MAT file should contain the following two arrays
          
          gyro : (3, N) float ndarray
                  The angular velocity measurements.
          timestamps : (N, ) float ndarray
                  Timestamps of the measurements.
                  
          Parameters
          ---------------
          matfilename : string
                  Name of the .mat file
          
          Returns
          ----------------
          A new IMU class instance