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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 find_importer_frame():
 """Returns the outer frame importing this "end" module. If this module is being imported by other means than import statement, None is returned. Returns: A frame object or None. """

    byte = lambda ch: ord(ch) if PY2 else ch
    frame = inspect.currentframe()
    try:
        while frame:
            code = frame.f_code
            lasti = frame.f_lasti
            if byte(code.co_code[lasti]) == dis.opmap['IMPORT_NAME']:
                # FIXME: Support EXTENDED_ARG.
                arg = (
                    byte(code.co_code[lasti + 1])
                    + byte(code.co_code[lasti + 2]) * 256)
                name = code.co_names[arg]
                if name == 'end':
                    break
                end
            end
            frame = frame.f_back
        end
        return frame
    finally:
        del frame
    end