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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 _valid_encoding(elt):
    '''Does this node have a valid encoding?
    '''
    enc = _find_encstyle(elt)
    if not enc or enc == _SOAP.ENC: return 1
    for e in enc.split():
        if e.startswith(_SOAP.ENC):
            # XXX Is this correct?  Once we find a Sec5 compatible
            # XXX encoding, should we check that all the rest are from
            # XXX that same base?  Perhaps.  But since the if test above
            # XXX will surely get 99% of the cases, leave it for now.
            return 1
    return 0