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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 extract_col_name(string):
 """ Take a string and split it. String will be a format like "presence_pass_azimuth", where "azimuth" is the MagIC column name and "presence_pass" is the validation. Return "presence", "azimuth". """

    prefixes = ["presence_pass_", "value_pass_", "type_pass_"]
    end = string.rfind("_")
    for prefix in prefixes:
        if string.startswith(prefix):
            return prefix[:-6], string[len(prefix):end]
    return string, string