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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 find_file(search_dir, file_pattern):
 """ Search for a file in a directory, and return the first match. If the file is not found return an empty string Args: search_dir: The root directory to search in file_pattern: A unix-style wildcard pattern representing the file to find Returns: The path to the file if it was found, otherwise an empty string """

    for root, dirnames, fnames in os.walk(search_dir):
            for fname in fnames:
                if fnmatch.fnmatch(fname, file_pattern):
                    return os.path.join(root, fname)
    return ""