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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 find_extensions(self, tag=None, namespace=None):
 """Searches extension elements for child nodes with the desired name. Returns a list of extension elements within this object whose tag and/or namespace match those passed in. To find all extensions in a particular namespace, specify the namespace but not the tag name. If you specify only the tag, the result list may contain extension elements in multiple namespaces. :param tag: str (optional) The desired tag :param namespace: str (optional) The desired namespace :Return: A list of elements whose tag and/or namespace match the parameters values """


        results = []

        if tag and namespace:
            for element in self.extension_elements:
                if element.tag == tag and element.namespace == namespace:
                    results.append(element)
        elif tag and not namespace:
            for element in self.extension_elements:
                if element.tag == tag:
                    results.append(element)
        elif namespace and not tag:
            for element in self.extension_elements:
                if element.namespace == namespace:
                    results.append(element)
        else:
            for element in self.extension_elements:
                results.append(element)

        return results