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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 tabActiveMarkupChanged(self, tab):
		'''
		Perform all UI state changes that need to be done when the
		active markup class of the current tab has changed.
		'''
		if tab == self.currentTab:
			markupClass = tab.getActiveMarkupClass()
			dtMarkdown = (markupClass == markups.MarkdownMarkup)
			dtMkdOrReST = dtMarkdown or (markupClass == markups.ReStructuredTextMarkup)
			self.formattingBox.setEnabled(dtMarkdown)
			self.symbolBox.setEnabled(dtMarkdown)
			self.actionUnderline.setEnabled(dtMarkdown)
			self.actionBold.setEnabled(dtMkdOrReST)
			self.actionItalic.setEnabled(dtMkdOrReST)