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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 create_lead(self, first_name, last_name, email=None, position=None, company=None, company_industry=None, company_size=None, confidence_score=None, website=None, country_code=None, postal_code=None, source=None, linkedin_url=None, phone_number=None, twitter=None, leads_list_id=None):
 """ Create a lead on your account. :param first_name: The first name of the lead to create. Must be defined. :param last_name: The last name of the lead to create. Must be defined. :param email: The email of the lead to create. :param position: The professional position of the lead to create. :param company: The company of the lead to create. :param company_industry: The type of industry of the company where the lead works. :param company_size: The size of the company where the lead works. :param confidence_score: The confidence score of the lead's email. :param website: The website of the lead's company. :param country_code: The country code of the lead's company. :param postal_code: The postal code of the lead's company. :param source: The source of the lead's email. :param linkedin_url: The URL of the lead's LinkedIn profile. :param phone_number: The phone number of the lead to create. :param twitter: The lead's Twitter account. :param leads_list_id: The id of the leads list where to save the new lead. :return: The newly created lead as a dict. """

        args = locals()
        payload = dict((key, value) for key, value in args.items() if value
                       is not None)
        payload.pop('self')

        params = self.base_params

        endpoint = self.base_endpoint.format('leads')

        return self._query_hunter(endpoint, params, 'post', payload)