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# get the fingerprint of a public key
ssh-keygen -l -E md5 -f  /PATH/TO/YOUR_PUBLIC_KEY.pub

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# get the fingerprint of a public key
ssh-keygen -l -E md5 -f  /PATH/TO/YOUR_PUBLIC_KEY.pub

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  for field in fields_iter:
      is_related_object = False
      # This slightly odd construct is so that we can access any
      # data-descriptor object (DeferredAttribute) without triggering its
      # __get__ method.
      if (field.attname not in kwargs and
              (isinstance(self.__class__.__dict__.get(field.attname), DeferredAttribute)
               or field.column is None)):
          # This field will be populated on request.
          continue

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class NameDescriptor:
    """
    NameDescriptor is a data descriptor because it implements __get__ and one of either __set__ or __del__
    """

    def __init__(self, name='Any Name'):
        print(f"\n__init__ called on NameDescriptor.")
        self.name: str = name

    def __get__(self, instance, klass) -> str:

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class Student:

    def __init__(self):
        print(f"\n__init__ called on Student.")

    def __getattribute__(self, key):
        print(f"\n__getattribute__ invoked on Student with key {key}")

        v = super(Student, self).__getattribute__(key)
        if hasattr(v, '__get__'):

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student = Student()
print(f"\nFirst access of name attribute on student: {student.name}")
student.__setattr__("name", "Yu Chen")
print(f"\n{student} instance symbol table: {student.__dict__}")
print(f"\nSecond access of name attribute on student: {student.name}")

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print(f"\nFirst access of grade attribute on student: {student.grade}")
student.__setattr__("grade", 12)
print(f"\n{student} instance symbol table: {student.__dict__}")
print(f"\nSecond access of grade attribute on student: {student.grade}")

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class ModelBase(type):
    a_variable_from_metaclass = 3
    _instances = dict() # keep track of the instances created per class

    @classmethod
    def __prepare__(metacls, name, bases, **kwargs):  # called first
        print(f"\nInside MetaClass __prepare__, name: {name}, bases: {bases}, metacls: {metacls}, kwargs: {kwargs}")
        namespace = super().__prepare__(name, bases, **kwargs)
        print(f"Returned namespace: {namespace}")
        return namespace

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class Model(metaclass=ModelBase):

    def __init__(self):
        print(f"Inside __init__ of Model with: {self}")
        super(Model, self).__init__() # object's __init__


class Student(Model):

    def __init__(self):

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if not abstract:
    new_class.add_to_class(
        'DoesNotExist',
        subclass_exception(
            'DoesNotExist',
            tuple(
                x.DoesNotExist for x in parents if hasattr(x, '_meta') and not x._meta.abstract
            ) or (ObjectDoesNotExist,),
            module,
            attached_to=new_class))