Given the following text documents, apply the text normalization process to get a normalized text. Assume your text normalization process contains the following steps: lowercasing, removing punctuation, tokenization, removing stop words, and stemming. Determine tokens, vocabulary, and types. Please show each step for each document. Build your combined tokens and vocabulary from the given documents, and determine the total number of types, vocabulary, and tokens.

Doc $1$: "She sells sea shells by the seashore."

Doc $2$: "How much wood would a woodchuck chuck if a woodchuck could chuck wood?"

Doc $3$: "A journey of a thousand miles begins with a single step."

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