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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 exists(self, path=None, client_kwargs=None, assume_exists=None):
 """ Return True if path refers to an existing path. Args: path (str):
 Path or URL. client_kwargs (dict):
 Client arguments. assume_exists (bool or None):
 This value define the value to return in the case there is no enough permission to determinate the existing status of the file. If set to None, the permission exception is reraised (Default behavior). if set to True or False, return this value. Returns: bool: True if exists. """

        try:
            self.head(path, client_kwargs)
        except ObjectNotFoundError:
            return False
        except ObjectPermissionError:
            if assume_exists is None:
                raise
            return assume_exists
        return True