Why can't I specify multiple types in a List in pydantic

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• Python File Tagging System does not retrieve nested dictionaries in dictionary

  I am building a file tagging system using Python. The idea is simple. Given a directory of files (and files within subdirectories), I want to filter them out using a filter input and tag those files with a word or a phrase.

  If I got the following contents in my current directory:

  data/
     budget.xls
     world_building_budget.txt
  a.txt
  b.exe
  hello_world.dat
  world_builder.spec
  

  and I execute the following command in the shell:

  py -3 tag_tool.py -filter=world -tag="World-Building Tool"
  

  My output will be:

  These files were tagged with "World-Building Tool":
  data/ world_building_budget.txt
  hello_world.dat
  world_builder.spec
  

  My current output isn't exactly like this but basically, I am converting all files and files within subdirectories into a single dictionary like this:

  def fs_tree_to_dict(path_):
      file_token = ''
      for root, dirs, files in os.walk(path_):
          tree = {d: fs_tree_to_dict(os.path.join(root, d)) for d in dirs}
          tree.update({f: file_token for f in files})
          return tree
  

  Right now, my dictionary looks like this: key:''.

  In the following function, I am turning the empty values '' into empty lists (to hold my tags):

  def empty_str_to_list(d):
      for k,v in d.items():
          if v == '':
              d[k] = []
          elif isinstance(v, dict):
              empty_str_to_list(v)
  

  When I run my entire code, this is my output:

  hello_world.dat ['World-Building Tool']
  world_builder.spec ['World-Building Tool']
  

  But it does not see data/world_building_budget.txt. This is the full dictionary:

  {'data': {'world_building_budget.txt': []},  
  'a.txt': [],
  'hello_world.dat': [], 
  'b.exe': [], 
  'world_builder.spec': []}
  
  

  This is my full code:

  import os, argparse
  
  
  def fs_tree_to_dict(path_):
      file_token = ''
      for root, dirs, files in os.walk(path_):
          tree = {d: fs_tree_to_dict(os.path.join(root, d)) for d in dirs}
          tree.update({f: file_token for f in files})
          return tree
  
  
  def empty_str_to_list(d):
      for k, v in d.items():
          if v == '':
              d[k] = []
          elif isinstance(v, dict):
              empty_str_to_list(v)
  
  
  parser = argparse.ArgumentParser(description="Just an example", formatter_class=argparse.ArgumentDefaultsHelpFormatter)
  
  parser.add_argument("--filter", action="store", help="keyword to filter files")
  parser.add_argument("--tag", action="store", help="a tag phrase to attach to a file")
  parser.add_argument("--get_tagged", action="store", help="retrieve files matching an existing tag")
  
  args = parser.parse_args()
  
  filter = args.filter
  tag = args.tag
  get_tagged = args.get_tagged
  current_dir = os.getcwd()
  
  files_dict = fs_tree_to_dict(current_dir)
  empty_str_to_list(files_dict)
  
  for k, v in files_dict.items():
      if filter in k:
          if v == []:
              v.append(tag)
              print(k, v)
  
          elif isinstance(v, dict):
              empty_str_to_list(v)
  
      if get_tagged in v:
          print(k, v)
  
• Actaully i am working on a project and in it, it is showing no module name pip_internal plz help me for the same. I am using pycharm(conda interpreter

   File "C:\Users\pjain\AppData\Local\Programs\Python\Python310\lib\runpy.py", line 196, in _run_module_as_main
      return _run_code(code, main_globals, None,
    File "C:\Users\pjain\AppData\Local\Programs\Python\Python310\lib\runpy.py", line 86, in _run_code
      exec(code, run_globals)
    File "C:\Users\pjain\AppData\Local\Programs\Python\Python310\Scripts\pip.exe\__main__.py", line 4, in <module>
    File "C:\Users\pjain\AppData\Local\Programs\Python\Python310\lib\site-packages\pip\_internal\__init__.py", line 4, in <module>
      from pip_internal.utils import _log
  

  I am using pycharm with conda interpreter.

  
• Looping the function if the input is not string

  I'm new to python (first of all) I have a homework to do a function about checking if an item exists in a dictionary or not.

  inventory = {"apple" : 50, "orange" : 50, "pineapple" : 70, "strawberry" : 30}
  
  def check_item():
      x = input("Enter the fruit's name: ")
      if not x.isalpha():
          print("Error! You need to type the name of the fruit")
      elif x in inventory:
          print("Fruit found:", x)
          print("Inventory available:", inventory[x],"KG")
      else:
          print("Fruit not found")
  check_item()
  

  I want the function to loop again only if the input written is not string. I've tried to type return Under print("Error! You need to type the name of the fruit") but didn't work. Help
• Is there a way to keep type inference in union types from type guards inside a function?

  Let's say I have three types (and a union one)

  type A = {
      type: 'a'
      title: string
      description: string
  }
  
  type B = {
      type: 'b'
      title: string
  }
  
  type C = {
      type: 'c'
      description: string
  }
  
  type D = A | B | C
  

  I know I can get a correct type inference with the === operator

  function logger(t: D) {
      if (t.type === 'a' || t.type === 'b') console.log(t.title) // no problems here
      if (t.type === 'a' || t.type === 'c') console.log(t.description) // no problems here
  }
  

  However, would it be possible to write an utility function:

  function matches<T extends { type: string }>(t: T, types: T['type'][]) : boolean {
      return types.includes(t.type)
  }
  

  So I can do this without errors?

  function logger(t: D) {
      if (matches(t, ['a', 'b'])) console.log(t.title) // Property 'title' does not exist on type D
      if (matches(t, ['a', 'c'])) console.log(t.description) // Property 'description' does not exist on type D
  }
  
• Alternative to index signature

  I have an array of object like this:

  [
    {
      "bio": "Douglas Gerald Hurley is an American engineer, former Marine Corps pilot and former NASA astronaut. He launched into space for the third time as commander of Crew Dragon Demo-2.",
      "images": {
        "png": "./assets/crew/image-douglas-hurley.png",
        "webp": "./assets/crew/image-douglas-hurley.webp"
      },
      "name": "Douglas Hurley",
      "role": "Commander"
    },
    {
      "bio": "Mark Richard Shuttleworth is the founder and CEO of Canonical, the company behind the Linux-based Ubuntu operating system. Shuttleworth became the first South African to travel to space as a space tourist.",
      "images": {
        "png": "./assets/crew/image-mark-shuttleworth.png",
        "webp": "./assets/crew/image-mark-shuttleworth.webp"
      },
      "name": "Mark Shuttleworth",
      "role": "Mission Specialist"
    },
    {
      "bio": "Pilot on the first operational flight of the SpaceX Crew Dragon to the International Space Station. Glover is a commander in the U.S. Navy where he pilots an F/A-18.He was a crew member of Expedition 64, and served as a station systems flight engineer.",
      "images": {
        "png": "./assets/crew/image-victor-glover.png",
        "webp": "./assets/crew/image-victor-glover.webp"
      },
      "name": "Victor Glover",
      "role": "Pilot"
    },
    {
      "bio": "Anousheh Ansari is an Iranian American engineer and co-founder of Prodea Systems. Ansari was the fourth self-funded space tourist, the first self-funded woman to fly to the ISS, and the first Iranian in space.",
      "images": {
        "png": "./assets/crew/image-anousheh-ansari.png",
        "webp": "./assets/crew/image-anousheh-ansari.webp"
      },
      "name": "Anousheh Ansari",
      "role": "Flight Engineer"
    }
  ]
  

  I typed that with index signature:

      export type PlanetInfo = {
        [key: string]: string;
      }[];
  

  but of course there are also the key "images" that are objects, I resolve that behaviour with:

      export type PlanetInfo = {
            [key: string]: any;
          }[];
  

  but I don't think the use of 'any' is correct. Is there a better way?
• how to make an iterable type in type script that has a key value pair

  I am using type script and I want to make a type that represents an object like this the keys generated are genrated dynamically how do I do that

  {  dog:true,
  cat:true,
  x:true
  }
  

  currently I am just using any but I woud like a proper type

   const matches: any= {}
  

  i get this error when i try to use

  
   {[key: string]: boolean}
  

  Type 'string[] | { [key: string]: boolean; }' must have a '[Symbol.iterator]()' method that returns an iterato
  

  code that causes this error

  const docgetter=()=>
      const matches: { [key: string]: boolean } = {}
      const documentFieldKeys = Array.isArray(documentNames) ? documentNames : Object.keys(documentNames)
    
  
      return [matches, documentFieldKeys]
  
  }
  
  
  
  const [matches,kycKeys]=docgetter()
  
  for(key of kycKeys)
  
• Why does the type-hinting for enum show an error on VS Code?

  I've run into an issue where the expected return type (Enum) and the actual return type do not match, even though they should.

  The weird thing is that depending on the way that I write the return statement, the results are different.

  The following picture explains this better:

  

  class PaymentValidationStatus(Enum):
      ORDER_NOT_FOUND = auto()
      ALREADY_PAID = auto()
      PAYMENT_AMOUNT_DOEST_NOT_MATCH_ORDER_PRICE = auto()
      COULD_NOT_PAY_ORDER = auto()
      PAYMENT_OK = auto()
  
  
  def some() -> PaymentValidationStatus:
      return PaymentValidationStatus["PAYMENT_OK"]
  
  
  def some2() -> PaymentValidationStatus:
      return PaymentValidationStatus.PAYMENT_OK
  
• Hinting specific types for attributes in subclasses where parent can have many types

  I have a parent class Foo which has an attribute bar. It has two subclasses which each have bar as a different type: FooStr has bar as a str, and FooInt has bar as an int. Foo is an abstract base class.

  How can I hint the specific type of an attribute in subclasses where the parent can have many types?

  This is what I started with. The hinting for the subclasses FooStr and FooInt tells me bar is a union of str or int, not very useful.

  class Foo(abc.ABC):
      def __init__(self, bar: typing.Union[str, int], stuff):
          self.bar = bar
          self.stuff = stuff
  
  class FooStr(Foo):
      pass
  
  class FooInt(Foo):
      pass
  

  Next I tried hinting the types in the init methods of the subclasses, but the hinting for bar in the subclasses still shows the type as a union.

  class Foo(abc.ABC):
      def __init__(self, bar: typing.Union[str, int], stuff):
          self.bar = bar
          self.stuff = stuff
  
  class FooStr(Foo):
      def __init__(self, bar: str, stuff):
          super().__init__(self, bar, stuff)
  
  class FooInt(Foo):
      def __init__(self, bar: int, stuff):
          super().__init__(self, bar, stuff)
  

  Then I tried removing bar from the parent init which hints the correct types for the subclasses, but not defining bar in the parent class Foo seems incorrect to me.

  class Foo(abc.ABC):
      def __init__(self, stuff):
          self.stuff = stuff
  
  class FooStr(Foo):
      def __init__(self, bar: str, stuff):
          self.bar = bar
          super().__init__(self, stuff)
  
  class FooInt(Foo):
      def __init__(self, bar: int, stuff):
          self.bar = bar
          super().__init__(self, stuff)
  

  Not sure where to go from here...
• Is it possible to extend pydantic models generated using datamodel-code-generator?

  I am using the datamodel-code-generator to generate pydantic models from a JSON schema.

  Here is the JSON schema used.

  And the generated models after running the datamodel-code-generator.

  # File: datamodel.py
  from __future__ import annotations
  from typing import List
  from pydantic import BaseModel
  
  class Record(BaseModel):
      id: int
      name: str
  
  class Table(BaseModel):
      records: List[Record]
  
  class Globals(BaseModel):
      table: Table
  
  

  I've been trying to extend the generated classes with new attributes.

  # File: extensions.py
  import json
  from datamodel import Table, Globals
  
  class ExtendedTable(Table):
      def __init__(self, *args, **kwargs):
          super().__init__(*args, **kwargs)
          print('ExtendedTable Constructor')
  
          # Won't work because "ExtendedTable" object has no field "records_by_id"
          self.records_by_id = {record.id: record for record in self.records}
  
  class ExtendedGlobals(Globals):
      def __init__(self, table: ExtendedTable):
          super().__init__(table=table)
          print('ExtendedGlobals Constructor')
  
  if __name__ == '__main__':
      records = '''
      {
          "table": {
              "records": [{"id": 0, "name": "A"}, {"id": 1, "name": "B"}]
          }
      }
      '''
  
      content = json.loads(records)
  
      # Both won't call ExtendedTable.__init__()
      ExtendedGlobals(**content)
      ExtendedGlobals.parse_obj(content)
  
      ExtendedGlobals(table=ExtendedTable(**content['table']))
  

  However, I haven't found a way to make the Globals class use the extended definition of the table. Also, simply adding new fields to the subclass does not seem to work.

  Is there a way to extend these classes without having to modify the pydantic generated models? Or maybe another tool to generate Python code from JSON schema?
• How to django orm object to pydantic list object

  i'm using django channels and pydantic

  using django orm sync_to_async

  how to this django orm object to pydantic response

  class ExchangeRateSchema(BaseSchema):
      currency: str
      sales_rate: str
      fix_time: datetime
      created_at: datetime
  
      @validator("currency")
      def validate_currency(cls, v):
          return v.split()[0]
  
      @validator("fix_time")
      def validate_fix_time(cls, v):
          return v.strftime("%Y.%m.%d %H:%M")
  
   # query_set
  list(ExchangeRate.objects.filter(*args, **kwargs))
  

  How to this ExchangeRateSchema to list data

  [
        {
          "currency": "USA1",
          "sales_rate": "1150.40",
          "fix_time": "2022.05.06 08:54",
          "created_at": "2022-05-06T08:55:07.998Z"
        },
        {
          "currency": "USA2",
          "sales_rate": "1150.40",
          "fix_time": "2022.05.06 08:54",
          "created_at": "2022-05-06T08:55:07.998Z"
        }
  ]
  

  using other code ExchangeRateSchema

  ExchangeRate.objects.filter(*args, **kwargs).latest(latest)
  ExchangeRateSchema(**exchange.dict)
   {
      "currency": "USA",
      "sales_rate": "1150.40",
      "fix_time": "2022.05.06 08:54",
      "created_at": "2022-05-06T08:55:07.998Z"
    }
  
• How to do exact one-to-one match validation with pydantic model schema?

  How can I exactly match the Pydantic schema?

  The suggested method is to attempt a dictionary conversion to the Pydantic model but that's not a one-one match.

  I am using something similar for API response schema validation using pytest.

  class Model_actual(BaseModel):
     val1 : str
  
  dict_to_be_validated = {'val1':'Hello', 'val2':'World'}
     
  assert Model_actual(**dict_to_be_validated) is not None
  

  I am looking for this assertion to fail instead of pass because it this is not a one-to-one match.
• Python equivalent of `final field` in java in dataclass

  Is it possible to have something like

  class MyAbstract {
     final int myFieldSomebodyHasToDefine;
  }
  
  
  class MyAbstractImplementation extends MyAbstract {
     final int myFieldSomebodyHasToDefine = 5;
  }
  

  using dataclasses in python?
• How to change default values of dataclass attributes dynamically?

  I would like to know if it is possible to change (dynamically) a default argument value in a dataclass, to achieve something like this:

  from dataclasses import dataclass
  
  @dataclass
  class Foo:
      bar = "foobar"
  
  Foo.bar = "world"
  
  foo1 = Foo(bar="hello")  # foo1.bar = "hello"
  foo2 = Foo()  # foo2.bar = "world"
  
• Recursively creates dataclasses based in nested dictionary

  I have a dataclass called Config that is created through the properties and values of a dictionary. Since this dictionary can have nested dictionaries, i would like to make nested dictionaries as Config objects. Here is an example:

  ## Dummy example of a config dict
  data = {
    'a' : 1,
    'b' : [2,2,2],
    'c': {
      'c_1' : 3.1
    }
  }
  
  final_config = create_config(data)
  
  # Expected result
  Config(a=1, b=[2,2,2], c=Config(c_1=3.1) )
  
  

  Here is what i've came up, using dataclasses.make_dataclass:

  def _Config(params_dict):
    config = make_dataclass('Config', params_dict.keys())
    return config(**params_dict)
    
  def get_inner_dict(d):
      for _, v in d.items():
          if isinstance(v, dict):
              return get_inner_dict(v) 
          else:
              return _Config(**d)
  

  Unfortunately, this doesn't work because the recursion will try to create a dataclass object when it finds a single value. I feel like i'm in the right way, but couldn't figure out what needs to change.