Python empuje en una matriz si no existe
other_array=[1,2,3]
myarray=[1,2]
for item in other_array:
if not item in myarray:
myarray.append(item)
Friendly Hawk
other_array=[1,2,3]
myarray=[1,2]
for item in other_array:
if not item in myarray:
myarray.append(item)