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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 history(self):
        ''' show payment history
        '''
        url= 'https://coincheck.com/api/exchange/orders/transactions'
        headers = make_header(url,access_key=self.access_key,secret_key=self.secret_key)
        r = requests.get(url,headers=headers)
        return json.loads(r.text)