Is there a way to execute a command just after downloading the source code in a pipeline?

[tyoc213]

I have a case where I need to execute 1 command just after downloading the sourcecode from a pipeline in the build phase??? In particular I want to modify something on the source just after download

[Container] 2023/10/05 18:24:32 Waiting for agent ping
--
2 | [Container] 2023/10/05 18:24:33 Waiting for DOWNLOAD_SOURCE
3 | [Container] 2023/10/05 18:24:34 Phase is DOWNLOAD_SOURCE
4 | [Container] 2023/10/05 18:24:34 CODEBUILD_SRC_DIR=/codebuild/output/src3715493993/src
5 | [my command] I want my command to be executed here

It seems that modifying buildspec.yml with a pre_build doesnt get the command get executed just after download.

  pre_build:
    commands:
      - echo "pre build commands!!!!!!"

Normally this will show in line 5 of execution

2023/10/05 18:39:44 YAML location is xxxxxxxxxxxxxxxxx/buildspec.yml