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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 initialize(self, size=0):
 """Initialize file on storage and truncate to given size."""

        fs, path = self._get_fs()

        # Required for reliably opening the file on certain file systems:
        if fs.exists(path):
            fp = fs.open(path, mode='r+b')
        else:
            fp = fs.open(path, mode='wb')

        try:
            fp.truncate(size)
        except Exception:
            fp.close()
            self.delete()
            raise
        finally:
            fp.close()

        self._size = size

        return self.fileurl, size, None