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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def write(self, filename, content, overwrite=False):
        '''
        Write content to a file.

        :param str filename: The storage root-relative filename
        :param content: The content to write in the file
        :param bool overwrite: Whether to wllow overwrite or not
        :raises FileExists: If the file exists and `overwrite` is `False`
        '''
        if not self.overwrite and not overwrite and self.backend.exists(filename):
            raise FileExists()
        return self.backend.write(filename, content)