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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 add_source_root(self, path, langs=tuple(), category=SourceRootCategories.UNKNOWN):
 """Add the specified fixed source root, which must be relative to the buildroot. Useful in a limited set of circumstances, e.g., when unpacking sources from a jar with unknown structure. Tests should prefer to use dirs that match our source root patterns instead of explicitly setting source roots here. """

    self._trie.add_fixed(path, langs, category)