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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 _tchelper(tc_deps,evals,deps):
 	""" 	modifies graph in place 	"""

	for e in evals:
		if e in tc_deps: # we've already included it
			continue
		else:
			if e in deps: # has additional dependnecies
				tc_deps[e]=deps[e]
				# add to tc_deps the dependencies of the dependencies
				_tchelper(tc_deps,deps[e],deps)
	return tc_deps