func_load_options.py

# Gist for discussion: https://github.com/fchollet/keras/pull/8592#discussion_r153287881


# OPTION 1 - replace list comprehension with for loop:

def func_load(code, defaults=None, closure=None, globs=None):
    """Deserializes a user defined function.

    # Arguments
        code: bytecode of the function.
        defaults: defaults of the function.
        closure: closure of the function.
        globs: dictionary of global objects.

    # Returns
        A function object.
    """
    if isinstance(code, (tuple, list)):  # unpack previous dump
        code, defaults, closure = code
        if isinstance(defaults, list):
            defaults = tuple(defaults)
    if closure is not None:
        closure = list(closure)
        for k, closure_value in enumerate(closure):
            closure[k] = ensure_value_to_cell(closure_value)
        closure = tuple(closure)
    raw_code = codecs.decode(code.encode('ascii'), 'base64')
    code = marshal.loads(raw_code)
    if globs is None:
        globs = globals()
    return python_types.FunctionType(code, globs,
                                     name=code.co_name,
                                     argdefs=defaults,
                                     closure=closure)


# OPTION 2 - same as option 1, but also inlined ensure_value_to_cell:

def func_load(code, defaults=None, closure=None, globs=None):
    """Deserializes a user defined function.

    # Arguments
        code: bytecode of the function.
        defaults: defaults of the function.
        closure: closure of the function.
        globs: dictionary of global objects.

    # Returns
        A function object.
    """
    if isinstance(code, (tuple, list)):  # unpack previous dump
        code, defaults, closure = code
        if isinstance(defaults, list):
            defaults = tuple(defaults)
    if closure is not None:
        closure = list(closure)
        for k, closure_value in enumerate(closure):
            def dummy_fn():
                closure_value  # just access it so it gets captured in .__closure__
            closure_value_as_cell = dummy_fn.__closure__[0]
            if not isinstance(closure_value, type(closure_value_as_cell)):
                closure[k] = closure_value_as_cell
        closure = tuple(closure)
    raw_code = codecs.decode(code.encode('ascii'), 'base64')
    code = marshal.loads(raw_code)
    if globs is None:
        globs = globals()
    return python_types.FunctionType(code, globs,
                                     name=code.co_name,
                                     argdefs=defaults,
                                     closure=closure)