You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: interceptor.go
    path of file: ./repos/eagle/pkg/transport/grpc
    
    the code of the file until where you have to start completion: package grpc

import (
	"context"

	"google.golang.org/grpc"
	"google.golang.org/grpc/metadata"
)

var (
	MetadataClientAPIVersionKey = "client-api-version"
)

// unaryServerInterceptor server unary interceptor
func unaryServerInterceptor(s *Server) grpc.UnaryS
    
func unaryClientInterceptor() grpc.UnaryClientInterceptor {
	return func(ctx context.Context, method string, req, reply interface{}, cc *grpc.ClientConn, invoker grpc.UnaryInvoker, opts ...grpc.CallOption) error {
		// preprocess stage

		// call remote method
		err := invoker(ctx, method, req, reply, cc, opts...)

		// postprocess stage

		return err
	}
}