This error is being generated because you are trying to import the module py package teste, or at least, that’s how the interpreter understands.
In Python language you should not put the file extension when importing the module. So your code should be like this:
import teste
teste.ipynb.path.insert('teste.py', "C:\Users\pasta\Documents\WPy64-3760\notebooks")
In addition, the point . is used to inform Python that an X module is within a certain package. See the example below:
# Árvore de diretórios:
#
# carro/
# carro/config/
# carro/config/motor.py
# carro/roda.py
# carro/volante.py
# piloto.py
import carro.config.motor # Importa o módulo "motor.py" do pacote "carro/config"
import carro.roda # Importa o módulo "roda.py" do pacote carro
import carro.volante # Importa o módulo "volante.py" do pacote carro
import piloto # Importa o módulo "piloto.py" que está no diretório atual
To learn more about Python import see this another answer.