class_docstr: Class to wrap MINC1 format opened netcdf object
  
  Although it has some of the same methods as a ``Header``, we use
  this only when reading a MINC file, to pull out useful header
  information, and for the method of reading the data out
code: def get_data_dtype(self):
      typecode = self._image.typecode()
      if typecode == "f":
          dtt = np.dtype(np.float32)
      elif typecode == "d":
          dtt = np.dtype(np.float64)
      else:
          signtype = self._image.signtype.decode("latin-1")
          dtt = _dt_dict[(typecode, signtype)]
      return np.dtype(dtt).newbyteorder(">")
  
imports: from __future__ import annotations
  from numbers import Integral
  import numpy
  from .externals.netcdf import netcdf_file
  from .fileslice import canonical_slicers
  from .spatialimages import SpatialHeader, SpatialImage
label_desc: Use image node_id 3 for calling the Minc1File obj's underlying member method code with example usage: obj.get_data_dtype() and returns: np