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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 _set_trusted_option_if_needed(repostr, trusted):
    '''
    Set trusted option to repo if needed
    '''
    if trusted is True:
        repostr += ' [trusted=yes]'
    elif trusted is False:
        repostr += ' [trusted=no]'
    return repostr