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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 receive_verify_post(self, post_params):
 """ Returns true if the incoming request is an authenticated verify post. """

        if isinstance(post_params,  dict):
            required_params = ['action', 'email', 'send_id', 'sig']
            if not self.check_for_valid_postback_actions(required_params, post_params):
                return False
        else:
            return False

        if post_params['action'] != 'verify':
            return False

        sig = post_params['sig']
        post_params = post_params.copy()
        del post_params['sig']

        if sig != get_signature_hash(post_params, self.secret):
            return False

        send_response = self.get_send(post_params['send_id'])

        try:
            send_body = send_response.get_body()
            send_json = json.loads(send_body)
            if 'email' not in send_body:
                return False
            if send_json['email'] != post_params['email']:
                return False
        except ValueError:
            return False

        return True