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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 source_files(mongodb_path):
 """Find source files."""

    for root, dirs, files in os.walk(mongodb_path):
        for filename in files:
            # skip files in dbtests folder
            if 'dbtests' in root:
                continue
            if filename.endswith(('.cpp', '.c', '.h')):
                yield os.path.join(root, filename)