Motion describes something that isn’t stopped, meaning not yet complete. This implies it’s more recent, or the conversion is more difficult than it should be.
Perhaps it’s already done, in which case this word choice is poor.
Perhaps it’s already done, in which case this word choice is poor.
It says "He has already put into motion the conversion of the Dropbox server code from Python 2 to Python 3. "
"already" refers to "sometime in the past 6 years".