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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 list_checks(self, limit=None, marker=None, return_next=False):
 """ Returns a list of the checks defined for this account. By default the number returned is limited to 100; you can define the number to return by optionally passing a value for the 'limit' parameter. The value for limit must be at least 1, and can be up to 1000. For pagination, you must also specify the 'marker' parameter. This is the ID of the first item to return. To get this, pass True for the 'return_next' parameter, and the response will be a 2-tuple, with the first element being the list of checks, and the second the ID of the next item. If there is no next item, the second element will be None. """

        checks = self._check_manager.list(limit=limit, marker=marker,
                return_next=return_next)
        for check in checks:
            check.set_entity(self)
        return checks