Unclear documentation for ObjectType

* **What is the current behavior?**

The current [documentation for ObjectType](https://docs.graphene-python.org/en/latest/types/objecttypes/) states the following under the "Parent Value Object" heading:

```
from graphene import ObjectType, String, Field

class Person(ObjectType):
full_name = String()

def resolve_full_name(parent, info):
return f"{parent.first_name} {parent.last_name}"

class Query(ObjectType):
me = Field(Person)

def resolve_me(parent, info):
# returns an object that represents a Person
return get_human(name="Luke Skywalker")
```

- **If the current behavior is a bug, please provide the steps to reproduce**

If you copy this directly into PyCharm (or any other editor I would imagine) you get an error stating that the function get_human cannot be located.

I am currently trying to write my own ObjectType which will take an argument. However, because the documentation cannot be run, I don't know how to proceed.

I have the following:

```
class RunLog(ObjectType):
status = String()
result = String()
log = List(String)

def resolve_status(self, resolve, run_id):
return r.hget("run:%i" % run_id, "status").decode('utf-8')

def resolve_result(self, resolve, run_id):
return r.hget("run:%i" % run_id, "result").decode('utf-8')

def resolve_log(self, resolve, run_id):
log_data = r.lrange("run:%i:log" % run_id, 0, -1)
log_data = [entry.decode('utf-8') for entry in log_data]

return log_data

class Query(ObjectType):
log_by_run_id = Field(RunLog, run_id=Int(required=True))

# @login_required
def resolve_log_by_run_id(root, info, run_id):
return **?????**
```

Because the documentation references an unknown function, I don't know what to put in the final line as the return value for resolve_log_by_run_id.

This type of unknown function of class seems to appear a lot in the documentation. It can be seen again under [Executing a query](https://docs.graphene-python.org/en/latest/execution/execute/#schemaexecute).

* **What is the expected behavior?**

The documentation can be clearly interoperated.

Start with the ObjectType documentation's “Parent Value Object” section and the “Executing a query” example linked in the issue. Review each undocumented function or placeholder and make the examples runnable or explain the required application-defined values, including what resolve_log_by_run_id should return. Done means a reader can interpret and follow the examples without unknown functions blocking them.

Vom Indexierungsmodell aus dem Issue-Text verfasst.