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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 islink(self, path=None, header=None):
 """ Returns True if object is a symbolic link. Args: path (str):
 File path or URL. header (dict):
 Object header. Returns: bool: True if object is Symlink. """

        if header is None:
            header = self._head(self.get_client_kwargs(path))

        for key in ('x-oss-object-type', 'type'):
            try:
                return header.pop(key) == 'Symlink'
            except KeyError:
                continue
        return False