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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 find(cls, where='.', exclude=(), include=('*',)):
 """Return a list all Python packages found within directory 'where' 'where' is the root directory which will be searched for packages. It should be supplied as a "cross-platform" (i.e. URL-style) path; it will be converted to the appropriate local path syntax. 'exclude' is a sequence of package names to exclude; '*' can be used as a wildcard in the names, such that 'foo.*' will exclude all subpackages of 'foo' (but not 'foo' itself). 'include' is a sequence of package names to include. If it's specified, only the named packages will be included. If it's not specified, all found packages will be included. 'include' can contain shell style wildcard patterns just like 'exclude'. """


        return list(cls._find_packages_iter(
            convert_path(where),
            cls._build_filter('ez_setup', '*__pycache__', *exclude),
            cls._build_filter(*include)))