def check(self, type_spec, arg_name, decorated_function):
		""" Return callable that checks function parameter for class validity. Checks parameter if it is
		class or subclass of specified class or classes

		:param type_spec: type or list/tuple/set of types
		:param arg_name: function parameter name
		:param decorated_function: target function
		:return: function
		"""

		def raise_exception(text_spec):
			exc_text = 'Argument "%s" for function "%s" has invalid type' % (
				arg_name, Verifier.function_name(decorated_function)
			)
			exc_text += ' (%s)' % text_spec
			raise TypeError(exc_text)

		if isinstance(type_spec, (tuple, list, set)):
			for single_type in type_spec:
				if (single_type is not None) and isclass(single_type) is False:
					raise RuntimeError(
						'Invalid specification. Must be type or tuple/list/set of types'
					)
			if None in type_spec:
				type_spec = tuple(filter(lambda x: x is not None, type_spec))
				return lambda x: None if \
					x is None or (isclass(x) is True and issubclass(x, type_spec) is True) else \
					raise_exception(str(x))
			else:
				return lambda x: None if (isclass(x) is True and issubclass(x, type_spec) is True) else \
					raise_exception(str(x))
		elif isclass(type_spec):
			return lambda x: None if (isclass(x) is True and issubclass(x, type_spec) is True) else \
				raise_exception(str(x))
		else:
			raise RuntimeError('Invalid specification. Must be type or tuple/list/set of types')
Return callable that checks function parameter for class validity. Checks parameter if it is
		class or subclass of specified class or classes

		:param type_spec: type or list/tuple/set of types
		:param arg_name: function parameter name
		:param decorated_function: target function
		:return: function