code: def write_data(self, data, dstart=None, reshape_order='C'):
          
          data = np.asarray(data).reshape(-1, order=reshape_order)
          if dstart is None:
              dstart = int(self.header_size)
          elif dstart < 0:
              raise ValueError('`dstart` must be non-negative, got {}'
                               ''.format(dstart))
          else:
              dstart = int(dstart)
  
          if dstart < self.header_size:
              raise ValueError('invalid `dstart`, resulting in absolute '
                               '`dstart` < `header_size` ({} < {})'
                               ''.format(dstart, self.header_size))
  
          self.file.seek(dstart)
          data.tofile(self.file)
docs: Write ``data`` to `file`.
  
          Parameters
          ----------
          data : `array-like`
              Data that should be written to `file`.
          dstart : non-negative int, optional
              Offset in bytes of the start position of the written data.
              By default, it is taken to be `header_size`.
          reshape_order : {'C', 'F', 'A'}, optional
              Value passed as ``order`` parameter to `numpy.reshape`.
              Reshaping is only done in case the whole data block is read.
  
          See Also
          --------
          write_header