import hashlib


def get_file_hash(filepath):
  """Reads the file and returns a SHA-1 hash of the file.

  Args:
    filepath: String of the path to the file to be hashed
  Returns:
    String: The SHA-1 hash of the file.
  """
  hasher = hashlib.sha1()
  blocksize = 65536
  with open(filepath, "rb") as f:
    buf = f.read(blocksize)
    while buf:
      hasher.update(buf)
      buf = f.read(blocksize)
  return hasher.hexdigest()