code: def __repr__(self):
      _, fmt = _formats[self.format]
      sparse_cls = "array" if isinstance(self, sparray) else "matrix"
      shape_str = "x".join(str(x) for x in self.shape)
      ndiag = self.data.shape[0]
      return (
          f"<{shape_str} sparse {sparse_cls} of type '{self.dtype.type}'\n"
          f"\twith {self.nnz} stored elements ({ndiag} diagonals) in {fmt} format>"
      )
  
imports: import numpy
  from ._matrix import spmatrix
  from ._base import issparse, _formats, _spbase, sparray
  from ._data import _data_matrix
  from ._sputils import isshape, upcast_char, getdtype, get_sum_dtype, validateaxis, check_shape
  from ._sparsetools import dia_matvec
label_desc: Use image node_id 2 for calling the _dia_base obj's underlying member method code with example usage: obj.__repr__() and returns: str, shape_str, str, sparse_cls, str, self, str, self, str, ndiag, str, fmt, str