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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 copy_contents(self, fileinstance, progress_callback=None, chunk_size=None, **kwargs):
 """Copy this file instance into another file instance."""

        if not fileinstance.readable:
            raise ValueError('Source file instance is not readable.')
        if not self.size == 0:
            raise ValueError('File instance has data.')

        self.set_uri(
            *self.storage(**kwargs).copy(
                fileinstance.storage(**kwargs),
                chunk_size=chunk_size,
                progress_callback=progress_callback))