ddate
convert Gregorian dates to Discordian dates
RUN apt-get update && \
apt-get install -y ddate
RUN apt-get update && \
apt-get install -y ddate
RUN apk add ddate
RUN apt-get update && \
apt-get install -y ddate
RUN yum install -y ddate
RUN dnf install -y ddate
RUN apt-get update && \
apt-get install -y ddate