[python] Update docs/ Markdown files for Classes to fix _form_ typo and correct casing for class name when calling from_dict()

[kdipippo]

All changes contained in 5385bcb
This only affects docs/ markdown files, so this is not a breaking change.

---

In the Python generated docs (for all three generators python, python-fastapi, and python-pydantic-v1), below is an example of what gets formed for the example snippet:

from openapi_client.models.dog_model import DogModel

# TODO update the JSON string below
json = "{}"
# create an instance of DogModel from a JSON string
dog_model_instance = DogModel.from_json(json)
# print the JSON string representation of the object
print(DogModel.to_json()) 

# convert the object into a dict
dog_model_dict = dog_model_instance.to_dict()
# create an instance of DogModel from a dict
dog_model_form_dict = dog_model.from_dict(dog_model_dict)  # <-- THIS LINE

Hovering over dog_model in the last row shows the error "dog_model" is not defined. The snippet works as expected if dog_model is instead DogModel, so that from_dict() is called against an empty object.

This also additionally changes dog_model_form_dict to dog_model_from_dict to match the method from_dict().

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Python Technical Committee

@cbornet (2017/09) @tomplus (2018/10) @krjakbrjak (2023/02) @fa0311 (2023/10) @multani (2023/10)

[fa0311]

LGTM, thanks!