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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def _help():
	'''Print all available tasks and descriptions.'''
	for task in sorted(TASKS, key=lambda x: (x.ns or '000') + x.name):
		tags = ''
		if task is DEFAULT:
			tags += '*'
		if task is SETUP:
			tags += '+'
		if task is TEARDOWN:
			tags += '-'

		print LOCALE['help_command'].format(task, tags, task.help)

		if task.aliases:
			print LOCALE['help_aliases'].format(task.aliasstr())
		if task.reqs:
			print LOCALE['help_reqs'].format(task.reqstr())
		if task.gens:
			print LOCALE['help_gens'].format(task.gens)
		if task.args or task.defaults:
			print LOCALE['help_args'].format(task.ns + task.name, task.kwargstr(), task.argstr())