docs: public AWSCredentials getCredentials(String profileName) {
          final AWSCredentialsProvider provider = credentialProviderCache.get(profileName);
          if (provider != null) {
              return provider.getCredentials();
          } else {
              BasicProfile profile = allProfiles.getProfile(profileName);
              if (profile == null) {
                  throw new IllegalArgumentException("No AWS profile named '" + profileName + "'");
              }
              final AWSCredentialsProvider newProvider = fromProfile(profile);
              credentialProviderCache.put(profileName, newProvider);
              return newProvider.getCredentials();
          }
      }