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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 suggest_filename(file_path, exists=None):
 """ Try if exist path and append number to its end. For debug you can set as input if file exists or not. """

    import os.path
    import re
    if not isinstance(exists, bool):
        exists = os.path.exists(file_path)

    if exists:
        file_path, file_extension = os.path.splitext(file_path)
        # print(file_path)
        m = re.search(r"_\d+$", file_path)
        if m is None:
            # cislo = 2
            new_cislo_str = "_2"
        else:
            cislostr = (m.group())
            cislo = int(cislostr[1:]) + 1
            # it is normal number
            file_path = file_path[:-len(cislostr)]
            new_cislo_str = "_" + str(cislo)

        file_path = file_path + new_cislo_str + file_extension  # .zfill(2)
        # trorcha rekurze
        file_path = suggest_filename(file_path)

    return file_path