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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 parse_parameters(self, parameters, array_class=None):
 """Parses a parameters arg to figure out what fields need to be loaded. Parameters parameters : (list of) strings The parameter(s) to retrieve. A parameter can be the name of any field in ``samples_group``, a virtual field or method of ``FieldArray`` (as long as the file contains the necessary fields to derive the virtual field or method), and/or a function of these. array_class : array class, optional The type of array to use to parse the parameters. The class must have a ``parse_parameters`` method. Default is to use a ``FieldArray``. Returns ------- list : A list of strings giving the fields to load from the file. """

        # get the type of array class to use
        if array_class is None:
            array_class = FieldArray
        # get the names of fields needed for the given parameters
        possible_fields = self[self.samples_group].keys()
        return array_class.parse_parameters(parameters, possible_fields)