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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 cli(ctx=None, verbose=0):
 """Thoth solver command line interface."""

    if ctx:
        ctx.auto_envvar_prefix = "THOTH_SOLVER"

    if verbose:
        _LOG.setLevel(logging.DEBUG)

    _LOG.debug("Debug mode is on")