dns.rdataset.DifferingCovers:
An attempt was made to add a DNS SIG/RRSIG whose covered type is
not the same as that of the other rdatas in the rdataset.
dns.rdtypes.mxbase.UncompressedMX:
Base class for rdata that is like an MX record, but whose name is
not compressed when converted to DNS wire format, and whose
digestable form is not downcased.
dns.rdtypes.nsbase.UncompressedNS:
Base class for rdata that is like an NS record, but whose name is
not compressed when convert to DNS wire format, and whose
digestable form is not downcased.
dict:
dict() -> new empty dictionary
dict(mapping) -> new dictionary initialized from a mapping object's
(key, value) pairs
dict(iterable) -> new dictionary initialized as if via:
d = {}
for k, v in iterable:
d[k] = v
dict(**kwargs) -> new dictionary initialized with the name=value pairs
in the keyword argument list.