master.py 文件源码

def scan_code_imports(co, LOAD_CONST=dis.opname.index('LOAD_CONST'),
                          IMPORT_NAME=dis.opname.index('IMPORT_NAME')):
    """Given a code object `co`, scan its bytecode yielding any
    ``IMPORT_NAME`` and associated prior ``LOAD_CONST`` instructions
    representing an `Import` statement or `ImportFrom` statement.

    :return:
        Generator producing `(level, modname, namelist)` tuples, where:

        * `level`: -1 for normal import, 0, for absolute import, and >0 for
          relative import.
        * `modname`: Name of module to import, or from where `namelist` names
          are imported.
        * `namelist`: for `ImportFrom`, the list of names to be imported from
          `modname`.
    """
    # Yield `(op, oparg)` tuples from the code object `co`.
    ordit = itertools.imap(ord, co.co_code)
    nextb = ordit.next

    opit = ((c, (None
                 if c < dis.HAVE_ARGUMENT else
                 (nextb() | (nextb() << 8))))
            for c in ordit)

    opit, opit2, opit3 = itertools.tee(opit, 3)
    next(opit2)
    next(opit3)
    next(opit3)

    for oparg1, oparg2, (op3, arg3) in itertools.izip(opit, opit2, opit3):
        if op3 == IMPORT_NAME:
            op2, arg2 = oparg2
            op1, arg1 = oparg1
            if op1 == op2 == LOAD_CONST:
                yield (co.co_consts[arg1],
                       co.co_names[arg3],
                       co.co_consts[arg2] or ())