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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_reqs(which="main"):
 """Gets requirements from all_reqs with versions."""

    reqs = []
    for req in all_reqs[which]:
        req_str = req + ">=" + ver_tuple_to_str(min_versions[req])
        if req in version_strictly:
            req_str += ",<" + ver_tuple_to_str(min_versions[req][:-1]) + "." + str(min_versions[req][-1] + 1)
        reqs.append(req_str)
    return reqs