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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 get_nameid_format(self):
 """ Gets the NameID Format provided by the SAML Response from the IdP :returns: NameID Format :rtype: string|None """

        nameid_format = None
        nameid_data = self.get_nameid_data()
        if nameid_data and 'Format' in nameid_data.keys():
            nameid_format = nameid_data['Format']
        return nameid_format