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Trouble with a context manager class made with dunders - Printable Version

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Trouble with a context manager class made with dunders - Regulus - Jan-28-2018

I am running Python 3.6.3 in Spyder 3.2 and getting 
Error:
TypeError: object() takes no parameters
at 
with ManagedFile('hello.txt') as f:
class ManagedFile:
    def _init_(self, name):
        self.name = name
    
    def _enter_(self):
        self.file = open(self.name, 'w')
        return self.file
    
    def _exit_(self, exc_type, exc_val, exc_tb):
        if self.file:
            self.file.close()

with ManagedFile('hello.txt') as f:
    f.write('hello there!')
    f.write('bye')
Obviously ManagedFile isn't a function that excepts parameters. But according to the author, _enter_ is supposed to work with the 
with
statement to enter its content. The last three lines are supposed to create a new file and write to it. The class is supposed to function as a "context manager," which is a new term to me. Is there something wrong you see in the code?

RE: Trouble with a context manager class made with dunders - Gribouillis - Jan-28-2018

(Jan-28-2018, 02:40 PM)Regulus Wrote: Is there something wrong you see in the code?
Yes there should be double underscores on each side for __init__, __enter__, exit__.