code: def isspmatrix_dia(x):
      """Is x of dia_matrix type?
  
      Parameters
      ----------
      x
          object to check for being a dia matrix
  
      Returns
      -------
      bool
          True if x is a dia matrix, False otherwise
  
      Examples
      --------
      >>> from scipy.sparse import dia_matrix, isspmatrix_dia
      >>> isspmatrix_dia(dia_matrix([[5]]))
      True
  
      >>> from scipy.sparse import dia_matrix, csr_matrix, isspmatrix_dia
      >>> isspmatrix_dia(csr_matrix([[5]]))
      False
      """
      return isinstance(x, dia_matrix)
  
imports: from __future__ import division, print_function, absolute_import
  import numpy
  from .base import isspmatrix, _formats, spmatrix
  from .data import _data_matrix
  from .sputils import isshape, upcast_char, getdtype, get_index_dtype, get_sum_dtype, validateaxis, check_shape, matrix
  from ._sparsetools import dia_matvec
label_desc: Use image node_id 1 for calling a global function with example usage: isspmatrix_dia(x) and returns: isinstance