numpy.save()function is used to store the input array in a disk file with npy extension(.npy).
Syntax : numpy.save(file, arr, allow_pickle=True, fix_imports=True)
file : : File or filename to which the data is saved. If file is a string or Path, a .npy extension will be appended to the file name if it does not already have one.If file is a file-object, then the filename is unchanged.
allow_pickle : : Allow saving object arrays using Python pickles. Reasons for disallowing pickles include security (loading pickled data can execute arbitrary code) and portability (pickled objects may not be loadable on different Python installations). Default: True
fix_imports : Only useful in forcing objects in object arrays on Python 3 to be pickled in a Python 2 compatible way.
arr : Array data to be saved.
Return : Stores the input array in a disk file with npy extension(.npy).
Code #1: Working
a is: [0 1 2 3 4] the array is saved in the file geekfile.npy
b is: [0 1 2 3 4] b is printed from geekfile.npy