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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 prefixedDec(nstr, schema):
 """ !~~prefixedDec corresponding strings in documents must begin with the associated string in the schema, and the right part of strings in documents must be decimal. """

    if not nstr.startswith(schema):
        return False
    postfix = nstr[len(schema):]
    try:
        int(postfix)
    except ValueError:
        return False
    return True