How to modify git log history

#!/bin/sh

cd ~/rails_workspace/MyAwsmProject;

git filter-branch --env-filter '
OLD_EMAIL="[email protected]"
CORRECT_NAME="foobar"
CORRECT_EMAIL="[email protected]"
if [ "$GIT_COMMITTER_EMAIL" = "$OLD_EMAIL" ]
then
    export GIT_COMMITTER_NAME="$CORRECT_NAME"
    export GIT_COMMITTER_EMAIL="$CORRECT_EMAIL"
fi
if [ "$GIT_AUTHOR_EMAIL" = "$OLD_EMAIL" ]
then
    export GIT_AUTHOR_NAME="$CORRECT_NAME"
    export GIT_AUTHOR_EMAIL="$CORRECT_EMAIL"
fi
' --force --tag-name-filter cat -- --branches --tags

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