class_docstr: Helper class for lazy (on-demand) loading of some external classes.
  
  The purpose of this class is to provide a way of testing against classes that either cannot be loaded immediately,
  or may not even be present on user's system. This class must be taught how to load each class of interest, and
  therefore should not be exposed to the user code. Instead use "singletons" ``h2oframe``, ``pandas_dataframe``,
  ``numpy_ndarray`` (and perhaps others in future). Usage::
  
      from h2o.utils.typechecks import assert_is_type, h2oframe, pandas_dataframe, numpy_ndarray
      assert_is_type(fr, h2oframe, pandas_dataframe, numpy_ndarray)
class_docstr_tok: ["Helper","class","for","lazy","(","on-demand",")","loading","of","some","external","classes",".","The","purpose","of","this","class","is","to","provide","a","way","of","testing","against","classes","that","either","can","not","be","loaded","immediately",",","or","may","not","even","be","present","on","user","'s","system",".","This","class","must","be","taught","how","to","load","each","class","of","interest",",","and","therefore","should","not","be","exposed","to","the","user","code",".","Instead","use","``","singletons","''","``","h2oframe","``",",","``","pandas_dataframe","``",",","``","numpy_ndarray","``","(","and","perhaps","others","in","future",")",".","Usage",":",":","from","h2o.utils.typechecks","import","assert_is_type",",","h2oframe",",","pandas_dataframe",",","numpy_ndarray","assert_is_type","(","fr",",","h2oframe",",","pandas_dataframe",",","numpy_ndarray",")"]
docstr: Return True if the variable matches this type, and False otherwise.
docstr_tok: ["Return","True","if","the","variable","matches","this","type",",","and","False","otherwise","."]
code: def check(self, var):
      """Return True if the variable matches this type, and False otherwise."""
      if self._class is None:
          self._init()
      return self._class and self._checker(var, self._class)
  
imports: from h2o.utils.compatibility import *
  import importlib
  import io
  import re
  import sys
  import tokenize
  from types import BuiltinFunctionType, FunctionType
  from h2o.exceptions import H2OTypeError, H2OValueError
label_desc: Use image node_id 2 for calling the _LazyClass obj's underlying member method code with example usage: obj.check(var) and returns: unknown