def stepSKIMPRODUCER(PhysicsSkims):
    """
    _stepSKIMPRODUCER_

    Creates and returns the configuration string for the SKIM step
    starting from the list of skims to be run.

    """

    step = ''
    if len(PhysicsSkims) >0 :
        step = ',SKIM:'+('+'.join(PhysicsSkims))
    return step