import maya.cmds as cmds

cubeList = cmds.ls("myCube*")
if len(cubeList) > 0:
    cmds.delete(cubeList)
    
result = cmds.polyCube (width=1, height=1, depth=1, name="myCube#")

# print ('result: ' + str(result))

transformName=result[0]

for i in range (0, 50) :
    
    instanceResult=cmds.instance(transformName, name=transformName + '_instance#')
    #print ('instanceResult:' + str (instanceResult))
    
    cmds.move(0, i, 0, instanceResult)