graphene/docs/pages/guide/mutation.md

# Mutations

A Mutation is a special ObjectType that define also an Input.

## Quick example

This example model defines a Mutation:

```python
import graphene

class CreatePerson(graphene.Mutation):
	class Input:
		name = graphene.String()

    ok = graphene.String()
    person = graphene.Field('Person')

    @classmethod
    def mutate(cls, args, info):
    	person = Person(name=args.get('name'))
    	ok = True
    	return CreatePerson(person=person, ok=ok)
```

**person** and **ok** are the output fields of the Mutation when is resolved.
**Input** attributes are the arguments that the Mutation needs for resolving. **mutate** is the function that will be applied once the mutation is called.

So, we can finish our schema like this:

```python
# ... the Mutation Class

class Person(graphene.ObjectType):
	name = graphene.String()

class MyMutations(graphene.ObjectType):
	create_person = graphene.Field(CreatePerson)

schema = graphene.Schema(mutation=MyMutations)
```

## Executing the Mutation

Then, if we query (`schema.execute(query_str)`) the following:
```graphql
mutation myFirstMutation {
	createPerson(name:"Peter") {
		person {
			name
		}
		ok
	}
}
```

We should receive:

```json
{
	"createPerson": {
		"person" : {
			name: "Peter"
		},
		"ok": true
	}
}