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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 _extract_secrets_from_patch(self, f, plugin, filename):
 """Extract secrets from a given patch file object. Note that we only want to capture incoming secrets (so added lines). :type f: unidiff.patch.PatchedFile :type plugin: detect_secrets.plugins.base.BasePlugin :type filename: str """

        output = {}
        for chunk in f:
            # target_lines refers to incoming (new) changes
            for line in chunk.target_lines():
                if line.is_added:
                    output.update(
                        plugin.analyze_string(
                            line.value,
                            line.target_line_no,
                            filename,
                        ),
                    )

        return output