HDF is a hierarchical data format developed by the National Center for Supercomputing Applications (NCSA)
to support Earth science data from NASA's Earth Observing System (EOS). The specific data structures that contain scientific data are: grid, swath, area average, and range.
Lets know how to open the file and read some important information.

import h5py
fname = r'MOP03J-20100801-L3V5.2.3.he5'
ff = h5py.File(fname, 'r')

Studying the structure of the file by printing what HDF5 groups are present

for key in ff.keys():
    print(key)

Names of the groups in HDF5 file.

Extracting the data

Get the HDF5 group

group = ff[key]

Checkout what keys are inside that group.

for key in group.keys():
    print(key)

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