$my_hash{"T::c"}

##</code><code>##

use Data::Dumper;

my %my_hash = (
    '"with_quotes_in_key"'  => 'a value',
    "without_quotes_in_key" => 'another value',
    bare_key                => 'a third value',
    "T::c"                  => 'your value',
    '"Another::thing"'      => 'a fifth value',
);

print Dumper \%my_hash;