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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 get_metadata(self, filename):
        '''Fetch all availabe metadata'''
        obj = self.bucket.Object(filename)
        checksum = 'md5:{0}'.format(obj.e_tag[1:-1])
        mime = obj.content_type.split(';', 1)[0] if obj.content_type else None
        return {
            'checksum': checksum,
            'size': obj.content_length,
            'mime': mime,
            'modified': obj.last_modified,
        }