code: def write(self, filename=None, io=None,
                coors=None, igs=None, out=None, float_format=None, **kwargs):
          
          if filename is None:
              filename = self.name + '.mesh'
  
          if io is None:
              io = self.io
              if io is None:
                  io = 'auto'
  
          if io == 'auto':
              io = MeshIO.any_from_filename( filename )
  
          if coors is None:
              coors = self.coors
  
          if igs is None:
              igs = range( len( self.conns ) )
  
          aux_mesh = Mesh.from_data( self.name, coors, self.ngroups,
                                     self.conns, self.mat_ids, self.descs, igs )
          io.set_float_format( float_format )
          io.write( filename, aux_mesh, out, **kwargs )
docs: Write mesh + optional results in `out` to a file.
  
          Parameters
          ----------
          filename : str, optional
              The file name. If None, the mesh name is used instead.
          io : MeshIO instance or 'auto', optional
              Passing 'auto' respects the extension of `filename`.
          coors : array, optional
              The coordinates that can be used instead of the mesh coordinates.
          igs : array_like, optional
              Passing a list of group ids selects only those groups for writing.
          out : dict, optional
              The output data attached to the mesh vertices and/or cells.
          float_format : str, optional
              The format string used to print floats in case of a text file
              format.
          **kwargs : dict, optional
              Additional arguments that can be passed to the `MeshIO` instance.