Creating an EditorPart for a .NET WebPart

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The other day I need to create a custom property field for a Web Part, this field needed to allow the users to select a value from a dynamically populated dropdown. After search across the internet for how to do this I found plenty of articles on creating a ToolPart which is used by SharePoint but this Web Part is part of a site that doesn't use SharePoint. The alternative on was an EditorPart which I will detail below.