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Solve the following problem using Python, implementing the functions described below, one line at a time
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<USER_TASK:>
Description:
 def _create_user(self, email, password, **extra_fields):
 """Create and save a User with the given email and password."""

        if not email:
            raise ValueError("The given email must be set")
        email = self.normalize_email(email)
        user = self.model(email=email, **extra_fields)
        user.set_password(password)
        user.save(using=self._db)
        return user