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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_color_definitions(data):
 """Returns the list of custom color definitions for the TikZ file. """

    definitions = []
    fmt = "\\definecolor{{{}}}{{rgb}}{{" + ",".join(3 * [data["float format"]]) + "}}"
    for name, rgb in data["custom colors"].items():
        definitions.append(fmt.format(name, rgb[0], rgb[1], rgb[2]))
    return definitions