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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 make_dep_graph(depender):
 	"""Returns a digraph string fragment based on the passed-in module 	"""

	shutit_global.shutit_global_object.yield_to_draw()
	digraph = ''
	for dependee_id in depender.depends_on:
		digraph = (digraph + '"' + depender.module_id + '"->"' + dependee_id + '";\n')
	return digraph