code: func PreparexContext(ctx context.Context, p PreparerContext, query string) (*Stmt, error) {
  	s, err := p.PrepareContext(ctx, query)
  	if err != nil {
  		return nil, err
  	}
  	return &Stmt{Stmt: s, unsafe: isUnsafe(p), Mapper: mapperFor(p)}, err
  }
docs: // PreparexContext prepares a statement.
  //
  // The provided context is used for the preparation of the statement, not for
  // the execution of the statement.