keyword - What is the use case for "pass" in Python? -


this question has answer here:

based on answers this question, pass keyword in python absolutely nothing. indicates "nothing done here."

given this, don't understand use of it. example, i'm looking @ following block of code while trying debug script else wrote:

def dccount(server):     ssh_cmd='ssh user@subserver.st%s' % (server)     cmd='%s "%s"' % (ssh_cmd, sub_cmd)     output=popen (cmd, shell=true, stdout=pipe)     result=output.wait()     queryresult=""     if result == 0:         queryresult = output.communicate()[0].strip()     else:         pass     takedata(server, "dc", queryresult)

is there purpose @ having else: pass here? in way change way function runs? seems if/else block rewritten following absolutely no change:

if result == 0:     queryresult = output.communicate()[0].strip() takedata(server, "dc", queryresult)

... or missing something? and, if i'm not missing something, why ever want use pass keyword @ all?

it indeed useless in example.

it helpful if want block empty, not otherwise allowed python. instance, when defining own exception subclass:

class myexception(exception):     pass

or maybe want loop on iterator side effects, nothing results:

for _ in iterator:     pass

but of time, won't need it.

remember if can add else isn't comment, may not need pass. empty function, instance, can take docstring , work block:

def nop():     """this function nothing, intentionally."""

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