Remove undefined variables in match.__main__()

[jeongyoonlee]

Proposed changes

This PR fixes #724 by removing undefined variables in match.__main__().

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• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
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Further comments

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[paullo0106]

thanks!