Where to dig potatoes? What does it mean to dig a sack?

The original words of this sentence are:

Where to dig potatoes, dig potatoes in the suburbs. One digs a sack, one digs a sack.

The source of this sentence is the cross talk content of a Spring Festival Gala. The pronunciation of this sentence "flower" is homophonic with the Japanese kana, so at first glance it feels like it is Japanese. In fact, it has no meaning and is purely for entertainment and comedy. The corresponding Japanese kana are as follows:

とどなにちわ, とどじょうちちわ, いわいまで, いわいまで.

Extended information:

Homophony is a Chinese vocabulary, pronounced as xié yīn. It takes advantage of the homophone or near-syllable conditions of Chinese characters to replace the original character with a homophone or near-syllable word to produce a word. Interesting figure of speech.

For example:

People also think that ‘Bashun’ is probably a nickname, while ‘Kento’ is a homophone. ——Mao Dun's "The Story of Hands" 2

Lake Waban has a similar homonym, so I called her "Weibing". ——Bing Xin's "For Young Readers" VII

Foods such as oranges and red dates use their homophonic sounds to bring good luck. ——Qin Mu "Lights on the Long Street·Beijing Spring Festival"

Reference: Baidu Encyclopedia - Homophone