code: def isspmatrix_dok(x):
      """Is x of dok_matrix type?
  
      Parameters
      ----------
      x
          object to check for being a dok matrix
  
      Returns
      -------
      bool
          True if x is a dok matrix, False otherwise
  
      Examples
      --------
      >>> from scipy.sparse import dok_matrix, isspmatrix_dok
      >>> isspmatrix_dok(dok_matrix([[5]]))
      True
  
      >>> from scipy.sparse import dok_matrix, csr_matrix, isspmatrix_dok
      >>> isspmatrix_dok(csr_matrix([[5]]))
      False
      """
      return isinstance(x, dok_matrix)
  
imports: from __future__ import division, print_function, absolute_import
  import functools
  import operator
  import itertools
  import numpy
  from scipy._lib.six import zip, xrange, iteritems, iterkeys, itervalues
  from .base import spmatrix, isspmatrix
  from .sputils import isdense, getdtype, isshape, isintlike, isscalarlike, upcast, upcast_scalar, IndexMixin, get_index_dtype, check_shape
label_desc: Use image node_id 1 for calling a global function with example usage: isspmatrix_dok(x) and returns: isinstance