from typing import Optional


def is_integer(param: Optional[str]) -> bool:
    """
    Function that returns if the string provided can represent an integer.
    This string can contain the sign of integer (+ for positive, - for negative)
    and could include whitespaces.

    Arguments
        param: str - value to check if it represents an integer string.

    Returns
        bool - True/False indicating if this condition is met
    """
    if param is None:
        return False
    try:
        float(param)
    except ValueError:
        return False
    else:
        return float(param).is_integer()