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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 parse_yaml(self, y):
        '''Parse a YAML spefication of an execution context into this
        object.

        '''
        self.id = y['id']
        self.kind = y['kind']
        if 'rate' in y:
            self.rate = float(y['rate'])
        else:
            self.rate = 0.0
        self._participants = []
        if 'participants' in y:
            for p in y.get('participants'):
                self._participants.append(TargetComponent().parse_yaml(p))
        if RTS_EXT_NS_YAML + 'properties' in y:
            for p in y.get(RTS_EXT_NS_YAML + 'properties'):
                if 'value' in p:
                    value = p['value']
                else:
                    value = None
                self._properties[p['name']] = value
        return self