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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 filter(self, pattern):
 """ Filter the results using a pattern. This accepts a shell-style wildcard pattern (as used by the fnmatch_ module):
: .copy() .pop() It also accepts a regular expression. This may be a compiled regular expression (from the re_ module) or a string that starts with a ``/`` (forward slash) character:: .clear() .count() .. _fnmatch: https://docs.python.org/3/library/fnmatch.html .. _re: https://docs.python.org/3/library/re.html """

        if isinstance(pattern, REGEX_TYPE):
            func = tools.filter_regex
        elif pattern.startswith('/'):
            pattern = re.compile(pattern.strip('/'))
            func = tools.filter_regex
        else:
            func = tools.filter_wildcard

        return SeeResult(func(self, pattern))