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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 valid_conkey(self, conkey):
 """Check that the conkey is a valid one. Return True if valid. A condition key is valid if it is one in the _COND_PREFIXES list. With the prefix removed, the remaining string must be either a number or the empty string."""


        for prefix in _COND_PREFIXES:
            trailing = conkey.lstrip(prefix)
            if trailing == '' and conkey:  # conkey is not empty
                return True
            try:
                int(trailing)
                return True
            except ValueError:
                pass

        return False