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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_internal_field_by_name(self, name):
 """Gets the field by name, or None if not found."""

        field = self._all_fields.get(name, self._all_fields.get('%s.%s' % (self._full_name, name)))
        if field is not None:
            return field
        for field_name in self._all_fields:
            # Specific name
            if field_name.endswith('.%s' % name):
                return self._all_fields[field_name]