import Blender

matlist = []

for material in Blender.Material.Get():
	if material.getName().find("Mat") <> -1:
		print "Mat :",material.getName()
		matlist.append(material)

object = Blender.Object.Get()
print object
bound = len(object)

for obj in range(bound):
	if object[obj].getName().find("Cyl") <> -1:
		index = int(Blender.Mathutils.Rand() * len(matlist))
		print "Obj :",object[obj].getName()
		object[obj].setMaterials(matlist[index])

Blender.Redraw()