| errors | Package errors implements functions to manipulate errors. |
| fmt | Package fmt implements formatted I/O with functions analogous to C's printf and scanf. |
| github.com/envoyproxy/go-control-plane/envoy/type/matcher/v3 | |
| google.golang.org/grpc/internal/grpcutil | Package grpcutil provides utility functions used across the gRPC codebase. |
| google.golang.org/grpc/metadata | Package metadata define the structure of the metadata supported by gRPC library. |
| regexp | Package regexp implements regular expression search. |
| strconv | Package strconv implements conversions to and from string representations of basic data types. |
| strings | Package strings implements simple functions to manipulate UTF-8 encoded strings. |