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I'm making a program that can access data stored inside a class. So for example I have this class:

#!/usr/bin/env python
import shelve

cur_dir = '.'

class Person:
    def __init__(self, name, score, age=None, yrclass=10):
        self.name = name
        self.firstname = name.split()[0]
        try:
            self.lastname = name.split()[1]
        except:
            self.lastname = None

        self.score = score
        self.age = age
        self.yrclass = yrclass
    def yrup(self):
        self.age += 1
        self.yrclass += 1

if __name__ == "__main__":
    db = shelve.open('people.dat')
    db['han'] = Person('Han Solo', 100, 37)
    db['luke'] = Person('Luke Skywalker', 83, 26)
    db['chewbacca'] = Person('Chewbacca', 100, 90901)

So using this I can call out a single variable like:

print db['luke'].name

But if I wanted to print all variables, I'm a little lost.

If I run:

f = db['han']
dir(f)

I get:

['__doc__', '__init__', '__module__', 'age', 'firstname', 'lastname', 'name', 'score', 'yrclass', 'yrup']

But I want to be able to print the actual data of those.

How can I do this?

Thanks in advance!

Fergus Barker
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8 Answers8

51
print db['han'].__dict__
DisplacedAussie
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28

Rather than using magic methods , Vars could be more preferable.

print(vars(db['han']))
Suresh2692
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13
print(vars(objectName))

Output:
{'m_var1': 'val1', 'm_var2': 'val2'}

This will print all the class variables with values initialised.

Andy K
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Archie Yalakki
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4

Define __str__ or __repr__ methods in your Person class and print the object.

EMPraptor
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2

Just try beeprint

after pp(db['han']), it will print this:

instance(Person):
    age: 37
    firstname: 'Han',
    lastname: 'Solo',
    name: 'Han Solo',
    score: 100,
    yrclass: 10

no methods, no private properties.

Anyany Pan
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1

If you want a method to print all the attribute, you can use:

def get_attribute(self):
    """
    Prints all attribute of object
    """

    for i in (vars(self)):
        print("{0:10}: {1}".format(i, vars(self)[i]))
    

You then need to call the method:

db['luke'].get_attribute()

and it will print:

name      : Luke Skywalker 
firstname : Luke 
lastname  : Skywalker 
score     : 83 
age       : 26 
yrclass   : 10

Please note you can play around with the value {0:10} to change the spacing for the columns.

LvM_
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0

print(vars(self)) or pprint(vars(self))

and to access self.variable name

Eg. self._own_name

user14678216
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0

If you want only the values of the variables you defined, you can do:

variables = [v for k, v in db['han'].__dict__.items() 
              
              # variable is not a python internal variable
              if not k.startswith("__") 
              and not k.endswith("__")
              
              # and is not a function
              and not "method" in str(v)
              and not "function" in str(v)]


print(variables) 
# ['Han Solo', 'Han', 'Solo', 100, 37, 10]

You will not print functions or internal Python variables (start and end with __), called dunders.

Vincent Claes
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