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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 hsetnx(self, key, field, value):
 """ Sets `field` in the hash stored at `key` only if it does not exist. Sets `field` in the hash stored at `key` only if `field` does not yet exist. If `key` does not exist, a new key holding a hash is created. If `field` already exists, this operation has no effect. .. note:: *Time complexity*: ``O(1)`` :param key: The key of the hash :type key: :class:`str`, :class:`bytes` :param field: The field in the hash to set :type key: :class:`str`, :class:`bytes` :param value: The value to set the field to :returns: ``1`` if `field` is a new field in the hash and `value` was set. ``0`` if `field` already exists in the hash and no operation was performed :rtype: int """

        return self._execute([b'HSETNX', key, field, value])