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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 validate_cbarpos(value):
 """Validate a colorbar position Parameters value: bool or str A string can be a combination of 'sh|sv|fl|fr|ft|fb|b|r' Returns ------- list list of strings with possible colorbar positions Raises ------ ValueError"""

    patt = 'sh|sv|fl|fr|ft|fb|b|r'
    if value is True:
        value = {'b'}
    elif not value:
        value = set()
    elif isinstance(value, six.string_types):
        for s in re.finditer('[^%s]+' % patt, value):
            warn("Unknown colorbar position %s!" % s.group(), RuntimeWarning)
        value = set(re.findall(patt, value))
    else:
        value = validate_stringset(value)
        for s in (s for s in value
                  if not re.match(patt, s)):
            warn("Unknown colorbar position %s!" % s)
            value.remove(s)
    return value