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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 stdlib(self):
 """ A boolean flag. ``True`` if frame is in stdlib. :type: bool """

        if self.module == 'pkg_resources' or self.module.startswith('pkg_resources.'):
            return False
        elif self.filename.startswith(SITE_PACKAGES_PATHS):
            # if it's in site-packages then its definitely not stdlib
            return False
        elif self.filename.startswith(SYS_PREFIX_PATHS):
            return True
        else:
            return False