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# HSETNX

> Write a field to a hash but only if the field does not exist.

## Arguments

<ParamField body="key" type="str" required>
  The key of the hash.
</ParamField>

<ParamField body="field" type="str" required>
  The name of the field.
</ParamField>

<ParamField body="value" type="Any" required>
  The value to set.
</ParamField>

## Response

<ResponseField type="bool" required>
  `True` if the field was set, `False` if it already existed.
</ResponseField>

<RequestExample>
```py Example
assert redis.hsetnx("myhash", "field1", "Hello") == True
assert redis.hsetnx("myhash", "field1", "World") == False
```
</RequestExample>