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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def sync( ctx, state, bare=False, user=False, unused=False, **kwargs ):
 """Installs all packages specified in Pipfile.lock."""

    from ..core import do_sync

    retcode = do_sync(
        ctx=ctx,
        dev=state.installstate.dev,
        three=state.three,
        python=state.python,
        bare=bare,
        dont_upgrade=(not state.installstate.keep_outdated),
        user=user,
        clear=state.clear,
        unused=unused,
        sequential=state.installstate.sequential,
        pypi_mirror=state.pypi_mirror,
    )
    if retcode:
        ctx.abort()