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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 load_ini(filename):
 """ Read a CLASS ``.ini`` file, returning a dictionary of parameters Parameters filename : str the name of an existing parameter file to load, or one included as part of the CLASS source Returns ------- dict : the input parameters loaded from file """

    # also look in data dir
    path = _find_file(filename)

    pars = {}
    with open(path, 'r') as ff:

        # loop over lines
        for lineno, line in enumerate(ff):
            if not line: continue

            # skip any commented lines with #
            if '#' in line: line = line[line.index('#')+1:]

            # must have an equals sign to be valid
            if "=" not in line: continue

            # extract key and value pairs
            fields = line.split("=")
            if len(fields) != 2:
                import warnings
                warnings.warn("skipping line number %d: '%s'" %(lineno,line))
                continue
            pars[fields[0].strip()] = fields[1].strip()

    return pars