def is_statement_in_list(statement, statement_list):
    """Return True of given statement is equivalent to on in a list

    Determines whether the statement is equivalent to any statement in the
    given list of statements, with equivalency determined by Statement's
    equals method.

    Parameters
    ----------
    statement : indra.statements.Statement
        The statement to compare with
    statement_list : list[indra.statements.Statement]
        The statement list whose entries we compare with statement

    Returns
    -------
    in_list : bool
        True if statement is equivalent to any statements in the list
    """
    for s in statement_list:
        if s.equals(statement):
            return True
    return False