E: Package 'python' has no installation candidate

While building a dockerfile image based on ubuntu:22.04, 'python' package is attempted to be downloaded as a package. However, this error is received during that process:

E: Package 'python' has no installation candidate
The command '/bin/sh -c apt-get update && DEBIAN_FRONTEND=noninteractive apt-get install -y gcc flex bison gettext grep iproute2 iptables make pkgconf python python3-pip && apt-get clean -y' returned a non-zero code: 100

My system's specifications are:
Distributor ID: Ubuntu
Description: Ubuntu 20.04.4 LTS
Release: 20.04
Codename: focal

--------------------
Part of Dockerfile:

FROM ubuntu:22.04

RUN apt-get update \
    && DEBIAN_FRONTEND=noninteractive apt-get install -y\
    gcc \
    flex \
    bison \
    gettext \
    grep \
    iproute2 \
    iptables \
    make \
    pkgconf \
    python \
    python3-pip \
    && apt-get clean -y