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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 diff_string_templates(string_a, string_b):
 """ Determine the diff of two strings. Return an empty string if the strings are identical, and the diff output string if they are not. """

    s1 = string_a.strip().splitlines()
    s2 = string_b.strip().splitlines()
    diffs = unified_diff(s2, s1, fromfile='deployed', tofile='local', lineterm='')
    return '\n'.join(diffs)