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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 grok_template_file(src):
 """Determine the real deal template file"""

    if not src.startswith('builtin:'):
        return abspath(src)

    builtin = src.split(':')[1]
    builtin = "templates/%s.j2" % builtin
    return resource_filename(__name__, builtin)