httppeer: properly gate debug usage behind debug flag check The "dbg" local variable is only defined if the 'debugflag' is set to True. However, it was used indiscriminately later in the function. We hide its usage behind the 'debugflag' value to avoid raising a NameError.

push: continue without locking on lock failure other than EEXIST (issue5882) This code was added by 3f5e75c22585 "push: make locking of source optional (issue3684)", but EACCES isn't the only error that could be triggered by filesystem permission. I think catching LockUnavailable is more appropriate than testing errno value by caller.