context_builder.go
func (cb *ContextBuilder) SetShardKey(sk string) *ContextBuilder {
	if cb.CallOptions == nil {
		cb.CallOptions = new(CallOptions)
	}
	cb.CallOptions.ShardKey = sk
	return cb
}
func (cb *ContextBuilder) SetShardKey(sk string) *ContextBuilder {
	if cb.CallOptions == nil {
		cb.CallOptions = new(CallOptions)
	}
	cb.CallOptions.ShardKey = sk
	return cb
}
// SetShardKey sets the ShardKey call option ("sk" transport header).