ZnFlow 0.1.9

What's Changed

• allow sum by @PythonFZ in #58
• fix IterableHandler updated by @PythonFZ in #60
• bump version by @PythonFZ in #61
• Fix sum by @PythonFZ in #63
• Update znflow.combine by @PythonFZ in #64
• replace assertion with ValueError by @PythonFZ in #49
• Add dict option to znflow.combine by @PythonFZ in #65
• fix RecursionError by @PythonFZ in #66
• Combine update by @PythonFZ in #67

Full Changelog: v0.1.6...v0.1.9