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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_relative_base_path(filename, path_to_check):
 """Extracts the relative mod path of the file to import from Check if a file is within the passed in path and if so, returns the relative mod path from the one passed in. If the filename is no in path_to_check, returns None Note this function will look for both abs and realpath of the file, this allows to find the relative base path even if the file is a symlink of a file in the passed in path Examples: _get_relative_base_path("/a/b/c/d.py", "/a/b") -> ["c","d"] _get_relative_base_path("/a/b/c/d.py", "/dev") -> None """

    importable_path = None
    path_to_check = os.path.normcase(path_to_check)
    abs_filename = os.path.abspath(filename)
    if os.path.normcase(abs_filename).startswith(path_to_check):
        importable_path = abs_filename

    real_filename = os.path.realpath(filename)
    if os.path.normcase(real_filename).startswith(path_to_check):
        importable_path = real_filename

    if importable_path:
        base_path = os.path.splitext(importable_path)[0]
        relative_base_path = base_path[len(path_to_check) :]
        return [pkg for pkg in relative_base_path.split(os.sep) if pkg]

    return None