ERROR: ep-dev-image-eaf-core-usb-update-1.0-r0 do_image_complete: Error executing a python function in exec_func_python() autogenerated:

The stack trace of python calls that resulted in this exception/failure was:
File: 'exec_func_python() autogenerated', lineno: 2, function: <module>
     0001:
 *** 0002:do_image_complete(d)
     0003:
File: '/home/user/Workspace/Yocto/my-machine/sources/poky/meta/classes/image.bbclass', lineno: 275, function: do_image_complete
     0271:    from oe.utils import execute_pre_post_process
     0272:
     0273:    post_process_cmds = d.getVar("IMAGE_POSTPROCESS_COMMAND")
     0274:
 *** 0275:    execute_pre_post_process(d, post_process_cmds)
     0276:}
     0277:do_image_complete[dirs] = "${TOPDIR}"
     0278:SSTATETASKS += "do_image_complete"
     0279:SSTATE_SKIP_CREATION:task-image-complete = '1'
File: '/home/user/Workspace/Yocto/my-machine/sources/poky/meta/lib/oe/utils.py', lineno: 263, function: execute_pre_post_process
     0259:    for cmd in cmds.strip().split(';'):
     0260:        cmd = cmd.strip()
     0261:        if cmd != '':
     0262:            bb.note("Executing %s ..." % cmd)
 *** 0263:            bb.build.exec_func(cmd, d)
     0264:
     0265:# For each item in items, call the function 'target' with item as the first
     0266:# argument, extraargs as the other arguments and handle any exceptions in the
     0267:# parent thread
File: '/home/user/Workspace/Yocto/my-machine/sources/poky/bitbake/lib/bb/build.py', lineno: 256, function: exec_func
     0252:    with bb.utils.fileslocked(lockfiles):
     0253:        if ispython:
     0254:            exec_func_python(func, d, runfile, cwd=adir)
     0255:        else:
 *** 0256:            exec_func_shell(func, d, runfile, cwd=adir)
     0257:
     0258:    try:
     0259:        curcwd = os.getcwd()
     0260:    except:
File: '/home/user/Workspace/Yocto/my-machine/sources/poky/bitbake/lib/bb/build.py', lineno: 507, function: exec_func_shell
     0503:    with open(fifopath, 'r+b', buffering=0) as fifo:
     0504:        try:
     0505:            bb.debug(2, "Executing shell function %s" % func)
     0506:            with open(os.devnull, 'r+') as stdin, logfile:
 *** 0507:                bb.process.run(cmd, shell=False, stdin=stdin, log=logfile, extrafiles=[(fifo,readfifo)])
     0508:        except bb.process.ExecutionError as exe:
     0509:            # Find the backtrace that the shell trap generated
     0510:            backtrace_marker_regex = re.compile(r"WARNING: Backtrace \(BB generated script\)")
     0511:            stdout_lines = (exe.stdout or "").split("\n")
File: '/home/user/Workspace/Yocto/my-machine/sources/poky/bitbake/lib/bb/process.py', lineno: 186, function: run
     0182:
     0183:    if pipe.returncode != 0:
     0184:        if log:
     0185:            # Don't duplicate the output in the exception if logging it
 *** 0186:            raise ExecutionError(cmd, pipe.returncode, None, None)
     0187:        raise ExecutionError(cmd, pipe.returncode, stdout, stderr)
     0188:    return stdout, stderr
Exception: bb.process.ExecutionError: Execution of '/home/user/Workspace/Yocto/my-machine/build/tmp/work/my-machine-fslc-linux/ep-dev-image-eaf-core-usb-update/1.0-r0/temp/run.eaf_deploy_update_firmware_image.20789' failed with exit code 1

ERROR: Logfile of failure stored in: /home/user/Workspace/Yocto/my-machine/build/tmp/work/my-machine-fslc-linux/ep-dev-image-eaf-core-usb-update/1.0-r0/temp/log.do_image_complete.20789
ERROR: Task (/home/user/Workspace/Yocto/my-machine/sources/meta-custom/recipes-custom/images/ep-dev-image-eaf-core-usb-update.bb:do_image_complete) failed with exit code '1'
NOTE: Tasks Summary: Attempted 5648 tasks of which 5632 didn't need to be rerun and 1 failed.
NOTE: Writing buildhistory
NOTE: Writing buildhistory took: 2 seconds

Summary: 1 task failed:
  /home/user/Workspace/Yocto/my-machine/sources/meta-custom/recipes-custom/images/ep-dev-image-eaf-core-usb-update.bb:do_image_complete
Summary: There was 1 ERROR message shown, returning a non-zero exit code.