non descriptive error

[Timothy Smith]

i have reproduced the error in this code block

#save values in edit
		self.FinaliseTill.SaveEditControlValue()
		if 
Decimal(self.parent.TillDetails[self.TillSelection.GetStringSelection()]['ChangeTinBalance'])) 
== Decimal('0'):
			#box must be checked before continuing
			if self.PlacedInSafe.GetValue() != 1:
				self.parent.Popup("You must place the till draw back in the 
safe","Till draw")
			else:
				#finalise the till draw
				if 	Decimal(self.TillFloat.GetLabel().split('$')[1]) != Decimal('0'):
					Prompt = wx.MessageDialog(self,"""The correct amount has not been 
returned from the till draw float to the main float!
					If you proceed please contact your manager""","Change tin doesn't 
balance!",wx.YES_NO)
					if Prompt.ShowModal() == wx.ID_YES:
						self.Submit()
		else:
			self.parent.Popup('You have an outstanding change tin balance on this 
till','Change tin')


i have NO idea what in there could be making it have such a strange 
error. it just says "error" when you try run it. there nothing terribly 
strange being done.