phonenumbers.go
func (c *IncomingNumberService) GetPageIterator(data url.Values) *IncomingPhoneNumberPageIterator {
	iter := NewPageIterator(c.client, data, numbersPathPart)
	return &IncomingPhoneNumberPageIterator{
		p: iter,
	}
}
func (c *IncomingNumberService) GetPageIterator(data url.Values) *IncomingPhoneNumberPageIterator {
	iter := NewPageIterator(c.client, data, numbersPathPart)
	return &IncomingPhoneNumberPageIterator{
		p: iter,
	}
}
// GetPageIterator returns an iterator which can be used to retrieve pages.