U-Boot

import os
import binascii

def file2env(file_name, addr=None):
    """Create dictionary describing file

    @filename:  name of the file to be described
    @addr:      address used for loading the file as int (e.g. 0x40400000)
    Return:     dictionary describing the file with entries
                * fn    - filename
                * size  - file size in bytes
                * crc32 - checksum using CRC-32 algorithm
                * addr  - loading address, optional
    """
    file_full = os.environ['UBOOT_TRAVIS_BUILD_DIR'] + "/" + file_name

    if not os.path.isfile(file_full):
        return None

    ret = {
        "fn": file_name,
        "size": os.path.getsize(file_full),
    }

    with open(file_full, 'rb') as fd:
        ret["crc32"] = hex(binascii.crc32(fd.read()) & 0xffffffff)[2:]

    if addr is not None:
        ret['addr'] = addr

    return ret