How Python imports code on GitHub, such as numpy

The phenomenon and background of the problem

because anaconda reinstall , It can not be used normally python Of
I am here GitHub Download it. numpy Source code

I unzipped this file into my project directory
But it cannot be called normally

Problem related code , Do not paste screenshots

# The first kind of code
import numpy as np
np.arange(9)

# The second code
import numpy.numpy as np
np.arange(9)

Operation results and error reporting contents

The result of the first code

The result of the first code

My solution ideas and tried methods

I don't know how to use GitHub Source code downloaded from ,readme It doesn't say how to use it

What I want to achieve

Sure import numpy as np success , have access to numpy This package