How to use the tockloader.app_tab.TabApp function in tockloader

# First get the TBF header from the correct binary in the TAB
			tbfh = TBFHeader(binary)

			if tbfh.is_valid():
				# Check that total size actually matches the binary that we got.
				if tbfh.get_app_size() < len(binary):
					# It's fine if the binary is smaller, but the binary cannot be
					# longer than the amount of reserved space (`total_size` in the
					# TBF header) for the app.
					raise TockLoaderException('Invalid TAB, the app binary is longer than its defined total_size')

				tbfs.append((tbfh, binary[tbfh.get_size_before_app():]))
			else:
				raise TockLoaderException('Invalid TBF found in app in TAB')

		return TabApp(tbfs)

tbf_filename = '{}.tbf'.format(tbf_name)
		binary_tarinfo = self.tab.getmember(tbf_filename)
		binary = self.tab.extractfile(binary_tarinfo).read()

		# First get the TBF header from the correct binary in the TAB
		tbfh = TBFHeader(binary)

		if tbfh.is_valid():
			# Check that total size actually matches the binary that we got.
			if tbfh.get_app_size() < len(binary):
				# It's fine if the binary is smaller, but the binary cannot be
				# longer than the amount of reserved space (`total_size` in the
				# TBF header) for the app.
				raise TockLoaderException('Invalid TAB, the app binary is longer than its defined total_size')

			return TabApp([(tbfh, binary[tbfh.get_size_before_app():])])
		else:
			raise TockLoaderException('Invalid TBF found in app in TAB')