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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 update(cls, customer_id, **kwargs):
 """ Static method defined to update paystack customer data by id. Args: customer_id: paystack customer id. first_name: customer's first name(optional). last_name: customer's last name(optional). email: customer's email address(optional). phone:customer's phone number(optional). Returns: Json data from paystack API. """

        return cls().requests.put('customer/{customer_id}'.format(**locals()),
                                  data=kwargs)