Python: AttributeError
In every programming language, if we develop new programs, there is a high chance of getting errors or exceptions. These errors yield to the program not being executed. One of the error in Python mostly occurs is “AttributeError”. AttributeError can be defined as an error that is raised when an attribute reference or assignment fails.
For example, if we take a variable x we are assigned a value of 10. In this process suppose we want to append another value to that variable. It’s not possible. Because the variable is an integer type it does not support the append method. So in this type of problem, we get an error called “AttributeError”. Suppose if the variable is list type then it supports the append method. Then there is no problem and not getting”Attribute error”.
Note: Attribute errors in Python are generally raised when an invalid attribute reference is made.
There are a few chances of getting AttributeError.
Example 1:
- Python3
Python3
# Python program to demonstrate# AttributeErrorX = 10# Raises an AttributeErrorX.append(6) |
Output:
Traceback (most recent call last):
File "/home/46576cfdd7cb1db75480a8653e2115cc.py", line 5, in
X.append(6)
AttributeError: 'int' object has no attribute 'append'
Example 2: Sometimes any variation in spelling will cause an Attribute error as Python is a case-sensitive language.
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Python3
# Python program to demonstrate# AttributeError# Raises an AttributeError as there is no# method as fst for stringsstring = "The famous website is { }".fst("geeksforgeeks")print(string) |
Output:
Traceback (most recent call last):
File "/home/2078367df38257e2ec3aead22841c153.py", line 3, in
string = "The famous website is { }".fst("geeksforgeeks")
AttributeError: 'str' object has no attribute 'fst'
Example 3: AttributeError can also be raised for a user-defined class when the user tries to make an invalid attribute reference.
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Python3
# Python program to demonstrate# AttributeErrorclass Geeks(): def __init__(self): self.a = 'GeeksforGeeks' # Driver's codeobj = Geeks()print(obj.a)# Raises an AttributeError as there# is no attribute b print(obj.b) |
Output:
GeeksforGeeks
Error:
Traceback (most recent call last):
File "/home/373989a62f52a8b91cb2d3300f411083.py", line 17, in
print(obj.b)
AttributeError: 'Geeks' object has no attribute 'b'
Example 4: AttributeError can also be raised for a user-defined class when the user misses out on adding tabs or spaces between their lines of code.
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Python3
#This is a dictionary parsing code written by Amit Jadhav #Because of an Indentation Error you will experience Attribute Errorclass dict_parsing: def __init__(self,a): self.a = a def getkeys(self): if self.notdict(): return list(self.a.keys()) def getvalues(self): if self.notdict(): return list(self.a.values()) def notdict(self): if type(self.a) != dict: raise Exception(self,a,'not a dictionary') return 1 def userinput(self): self.a = eval(input()) print(self.a,type(self.a)) print(self.getykeys()) print(self.getvalyes()) def insertion(self,k,v): self.a[k]=v d = dict_parsing({"k1":"amit", "k2":[1,2,3,4,5]})d.getkeys() |
Output:
--------------------------------------------------------------------------- AttributeError Traceback (most recent call last) <ipython-input-9-c26cd169473f> in <module> ----> 1 d.getkeys() AttributeError: 'dict_parsing' object has no attribute 'getkeys'
Error:
--------------------------------------------------------------------------- AttributeError Traceback (most recent call last) <ipython-input-9-c26cd169473f> in <module> ----> 1 d.getkeys() AttributeError: 'dict_parsing' object has no attribute 'getkeys'
Solution for AttributeError
Errors and exceptions in Python can be handled using exception handling i.e. by using try and except in Python.
Example: Consider the above class example, we want to do something else rather than printing the traceback Whenever an AttributeError is raised.
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Python3
# Python program to demonstrate # AttributeErrorclass Geeks(): def __init__(self): self.a = 'GeeksforGeeks'# Driver's codeobj = Geeks()# Try and except statement for # Exception handlingtry: print(obj.a) # Raises an AttributeError print(obj.b) # Prints the below statement# whenever an AttributeError is # raisedexcept AttributeError: print("There is no such attribute") |
Output:
GeeksforGeeks There is no such attribute
Note: To know more about exception handling click here.
