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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_d1_env_by_base_url(cn_base_url):
 """Given the BaseURL for a CN, return the DataONE environment dict for the CN's environemnt."""

    for k, v in D1_ENV_DICT:
        if v['base_url'].startswith(cn_base_url):
            return D1_ENV_DICT[k]