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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 set_value(self, name, value, ignore_error=False, block_user_signals=False):
 """ Sets the variable of the supplied name to the supplied value. Setting block_user_signals=True will temporarily block the widget from sending any signals when setting the value. """

        # first clean up the name
        name = self._clean_up_name(name)

        # If we're supposed to, block the user signals for this parameter
        if block_user_signals: self.block_user_signals(name, ignore_error)        

        # now get the parameter object
        x = self._find_parameter(name.split('/'), quiet=ignore_error)

        # quit if it pooped.
        if x == None: return None
        
        # for lists, make sure the value exists!!
        if x.type() in ['list']:
            
            # Make sure it exists before trying to set it
            if str(value) in list(x.forward.keys()): x.setValue(str(value))
            
            # Otherwise default to the first key
            else: x.setValue(list(x.forward.keys())[0])
        
        # Bail to a hopeful set method for other types
        else: x.setValue(eval(x.opts['type'])(value))

        # If we're supposed to unblock the user signals for this parameter
        if block_user_signals: self.unblock_user_signals(name, ignore_error)

        return self