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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 calculateLocalElasticitySegments(self, bp, span=2, frameGap=None, helical=False, unit='kT', err_type='block', tool='gmx analyze', outFile=None):
 """Calculate local elastic properties of consecutive overlapped DNA segments Calculate local elastic properties of consecutive overlapped DNA segments of length given by `span`. Parameters bp : list List of two base-steps forming the global DNA segment. For example: with ``bp=[5, 50]``, 5-50 base-step segment will be considered. span : int Length of overlapping (local) DNA segments. It should be less than four. frameGap : int How many frames to skip for next time-frame. Lower the number, slower will be the calculation. helical : bool If ``helical=True``, elastic matrix for **helical base-step** parameters are calculated. Otherwise, by default, elastic matrix for **base-step** parameters are calculated. unit : str Unit of energy. Allowed units are: ``'kT', 'kJ/mol' and 'kcal/mol'``. err_type : str Error estimation by autocorrelation method ``err_type='acf'`` or block averaging method ``err_type='block'`` tool : str GROMACS tool to calculate error. In older versions it is `g_analyze` while in newer versions (above 2016) it is `gmx analyze`. outFile : str Output file in csv format. Returns ------- segments : list list of DNA segments for which local elastic properties was calculated. elasticities : OrderedDict A ordered dictionary of 1D arrays of shape (segments). The keys in dictionary are name of the elasticity in the same order as listed above. error : OrderedDict A ordered dictionary of 1D arrays of shape (segments). The keys in dictionary are name of the elasticity in the same order as listed above.. """

        if helical:
            props_name = helical_local_props_vector
        else:
            props_name = local_props_vector

        segments, errors, elasticities = [], OrderedDict(), OrderedDict()
        for name in props_name:
            elasticities[name] = []
            errors[name] = []

        for s in range(bp[0], bp[1]):
            if s+span-1 > bp[1]:
                break
            time, elasticity_t = self.getLocalElasticityByTime([s, s+span-1], frameGap=frameGap, helical=helical, unit=unit)
            error_t = dnaMD.get_error(time, list(elasticity_t.values()), len(props_name), err_type=err_type, tool=tool)
            for i in range(len(props_name)):
                esy_t = elasticity_t[props_name[i]][-1]           # only take last entry
                elasticities[props_name[i]].append(esy_t)
                errors[props_name[i]].append(error_t[i])
            segments.append('{0}-{1}'.format(s, s+span-1))

        # Write output file
        if outFile is not None:
            with open(outFile, 'w') as fout:
                fout.write('#bps')
                for name in props_name:
                    fout.write(', {0}, {0}-error'.format(name))
                fout.write('\n')
                for s in range(len(segments)):
                    fout.write('{0}'.format(segments[s]))
                    for name in props_name:
                        fout.write(', {0:.5f}, {1:.5f}'.format(elasticities[name][s], errors[name][s]))
                    fout.write('\n')

        return segments, elasticities, errors